‘ For patients already battling Alzheimer’s disease, studies indicate that Covid can exacerbate brain inflammation, damage immune cells, and accelerate the memory-robbing disease itself.  Even previously healthy older adults face an increased risk of cognitive impairment and new-onset dementia after infection. Mild Covid cases in younger adults have also been linked to brain issues affecting memory and thinking. ’

‘Cognitive difficulties following COVID-19 infection appear to be long lasting. In the current study, impairment was observed up to 17 months post-infection – aligning with previous research in young adults, where impairments persisted for up to 10 months following COVID-19.’

‘But even people who had not been hospitalized had increased risks of many conditions, ranging from an 8% increase in the rate of heart attacks to a 247% increase in the rate of heart inflammation.’ Nature (2 Aug 2022) ‘Either symptomatic or asymptomatic SARS-CoV-2 infection is associated with increased risk of late cardiovascular outcomes and has causal effect on all-cause mortality in a late post-COVID-19 period.’ The American Journal of Cardiology (15 Sep 2023)

‘The proportions of PACS [PASC/Long Covid] patients experiencing chest pain, palpitation, and hypertension as sequelae were 22% , 18% , and 19% respectively.’

‘Before Omicron, natural infection provided strong and durable protection against reinfection, with minimal waning over time.  However, during the Omicron era, protection was robust only for those recently infected, declining rapidly over time and diminishing within a year.’

‘Scientists discover that even mild COVID-19 can alter brain proteins linked to Alzheimer’s disease, potentially increasing dementia risk. COVID-19-positive individuals exhibited lower cognitive test performance compared to controls – equivalent to almost two years of age-related cognitive decline. ’

‘The predominant symptoms , often clustering together, remain fatigue , cognitive disturbance and chest symptoms , including breathlessness , with sleep disorder and anxiety as additional complaints. Many patients with persistent PCS show impaired executive functioning , reduced cognitive processing speed and reduced physical exercise capacity .’

❦ On that 700-day cough... It’s a new thing, but it’s only reserved for inside supermarkets and offices. And pharmacies and hospitals and care homes. Oh, and your living-room. But apart from that, it’s not exactly a deal-breaker. I mean, c’mon. They put up with way worse in the 1800s. © 2024 C19.Life ❂

❦ “If you are letting yourself get infected and taking no precautions against passing it on, you are not a passive bystander for your next infection. You’ve participated in creating it.” ❂ © 2024 Dr. Noor Bari, Emergency Medicine .

❦ ‘In this population of healthy young adult US Marines with mostly either asymptomatic or mild acute COVID-19, one fourth reported physical , cognitive , or psychiatric long-term sequelae of infection. The Marines affected with PASC [Post-Acute Sequelae of COVID-19 / Post-COVID-19 Complications / ‘Long Covid’] showed evidence of long-term decrease in functional performance suggesting that SARS-CoV-2 infection may negatively affect health for a significant proportion of young adults .’ ❂ ‘Among the 899 participants, 88.8% had a SARS-CoV-2 infection. Almost a quarter (24.7%) of these individuals had at least one COVID-19 symptom that lasted for at least 4 weeks meeting the a priori definition of PASC established for this study. Among those with PASC, 10 had no acute SARS-CoV-2 symptoms after PCR-confirmed infection suggesting that PASC can occur among asymptomatic individuals. Many participants reported that lingering symptoms impaired their productivity at work, caused them to miss work, and/or limited their ability to perform normal duty/activities. Marines with PASC had significantly decreased physical fitness test scores up to approximately one year post-infection with a three-mile run time that averaged in the 65th percentile of the reference cohort. [ PASC was associated with a significantly increased 3-mile run time on the standard Marine fitness test. PASC participants ran 25.1 seconds slower than a pre-pandemic reference cohort composed of 22,612 Marine recruits from 2016 to 2019. A three-mile run evaluates aerobic exercise , overhead lifting of an ammunition can and pull-ups evaluate strength , and shooting a rifle evaluates fine-motor skills .] Scores for events evaluating upper body (pull-ups, crunches, and ammo-can lift) were not significantly reduced by PASC; however, overall physical fitness scores were reduced. ‘The poorer run times and overall scores among PASC participants are indicative of on-going functional effects.’ Standardized health-based assessments for somatization, depression, and anxiety further highlighted the detrimental health effects of PASC. Almost 10% of participants with PASC had PHQ-8 scores ≥10. Increased somatization * has been associated with increased stress, depression, and problems with emotions. * [ Somatization / Somatisation = Medical symptoms caused by psychological stress.] Additionally, PASC participants had higher GAD-7 scores suggesting increased anxiety in a population with unique inherent occupational stressors associated with higher rates of anxiety, depression, and post-traumatic stress disorder. ‘Increased severity of anxiety among those with PASC, combined with greater rates of mental health disorders in general, could portend an ominous combination and should be closely followed.’ Like others, we identified cardiopulmonary symptoms as some of the most prevalent. The high prevalence of symptoms like shortness of breath, difficulty breathing, cough, and fatigue is particularly notable when combined with decreased objective measures of aerobic performance such as running. These results suggest pathology in the cardiopulmonary system. In contrast we observed no reduction in scores assessing strength and marksmanship suggesting the lack of detectable pathology in the neuro-musculoskeletal system. We have previously found in this same cohort that SARS-CoV-2 infection causes prolonged dysregulation of immune cell epigenetic patterns like auto-immune diseases. Based on the reported PASC symptoms, the potential current and future public health implications in this population could be substantial. ‘Chronic health complications from PASC, especially in a young and previously healthy population with a long life expectancy, could decrease work productivity and increase healthcare costs.’ Significant changes in the Years-of-Life lived with a disability can disproportionally increase disability-adjusted life-years, and should be considered when allocating resources and designing policy.’ ❂ 📖 (23 Oct 2024 ~ The Lancet: Regional Health/America) Clinical and functional assessment of SARS-CoV-2 sequelae among young marines – a panel study ➤ © 2024 The Lancet .

❦ If parents, and politicians and teachers, and healthcare workers and public health bodies wanted things to change, all they need do is read . It’s all there. But they don’t. They won’t. And they insist on their medical and scientific flat-earthing – hand-sanitiser for aerosol-transmitted disease – because they prefer the world to be flat. So let them walk off the edge of the world. [ Caveat: The earth is not flat, and doing nothing will not flatten the curve – but walk far enough, and you are likely to fall off a cliff.] © 2024 C19.Life ❂

❦ NHS nurse: — “Shit, I just got a needlestick injury.” ❦ 2024: — “Yeah, well, whatever. We all gotta die of something.” ❂ © 2024 C19.Life .

‘In those school-rooms where ventilation is imperfect and the air impure, six sevenths of the money expended to educate a child is wasted.’ ❂ The Ventilation and Warming of School Buildings (1887) By Gilbert B. Morrison Published by D. Appleton and Company, New York. 1887. Accessed 10 Apr 2024 Preface (p.xxii) ❦ ‘I am fully convinced that people are prematurely dying by thousands simply from a lack of correct and positive convictions concerning impure air; for, when the true nature of a danger is fully appreciated, the requisite means to avert it will generally be found.’ ❂ Chapter II: The Effects Of Breathing Impure Air (pp.20-23) ❦ ‘Impure air is also believed by the best authorities to be one of the principal causes of epidemics. Dr. Carpenter, than whom there is no abler authority, says: “It is impossible for anyone who carefully examines the evidence to hesitate for a moment in the conclusion that the fatality of epidemics is almost invariably in precise proportion to the degree in which an impure atmosphere has been habitually respired.” The Board of Health of New York conclude that forty per cent of all deaths are caused by breathing impure air. In view of such alarming facts, this same board declares: “Viewing the causes of preventable diseases, and their fatal results, we unhesitatingly state that the first sanitary want in New York and Brooklyn is ventilation .” Direct experiment proves that the air in our school-rooms is impure in almost all cases, and in a majority of them to a degree far beyond the danger line. In view of these facts, and the results as proved by the authorities above cited, why is it regarded by the public with such indifference? When a school-house is blown down by a hurricane, killing and maiming a score of children, it is justly regarded as a great calamity; a vacation is given to quiet the excited fears of parents and children; investigating committees are appointed to locate the responsibility, and the faces of the whole populace are blanched with apprehension. Why is this? Why does the intelligent parent send his child to a school-room poorly ventilated and crowded with children, some of whom are breathing into a stagnant air the germs of disease and death, while others, from unwashed bodies, are delivering into it their deadly emanations, and all without a protest on the part of those even who provide proper hygienic conditions at home? It is because the effects of the one are immediate, occupy little time, the number killed can be actually counted, and the exact magnitude of the calamity estimated all at once. In the other case the process is slower, but of far greater extent; the actual results are by the general public less definitely known, and custom and attention to other matters divert the attention, and the deadly destruction of the innocents by impure air goes on silently, constantly, and powerfully. While noisy demonstrations like that of the cyclone attract attention, and inspire fear and terror, it is in the silent forces that the danger lies. Nature’s most destructive forces, as well as her strongest constructive ones, are silent in their operations; but when Science detects a silent, insidious enemy to human welfare, it is not only our duty to assume an attitude of self-defense and self-protection, but it should be regarded as folly not to do so.’ ❦ On high CO₂ levels connected to poor performance in schools: ‘The effects of breathing impure air thus far considered are pathological, but it has its pedagogical and economical aspects. Every observing teacher knows the immediate relation between the vitiated air in the school-room and the work he wishes the pupils to perform. Much of the disappointment of poor lessons and the tendency to disorder are due directly to this cause. The brain unsupplied with a proper amount of pure blood [oxygen] refuses to act, and the will is powerless to arouse the flagging energies; the general feeling of discomfort, dissatisfaction, and unrest which always accompanies a bad state of the blood. From an economical standpoint it would, of course, be impossible to estimate the financial waste of breathing impure air, but it can not but be enormous. In any discussion of the feasibility of incurring the additional expense of the most perfect ventilation, this loss occasioned by the want of such ventilation must not be ignored.’ ❂ Chapter III: The Air (pp.25-26) ❦ On ventilation, air filtration, and the super-spreading of diverse diseases in classrooms: ‘Wherever an unusual amount of unwholesome matter is being evolved, there especially should the purifying conditions be present; air in such places, to remain pure, must be changed in rapid succession, in order that dilution, diffusion, and oxidation may fulfill their legitimate functions. In a school-room the contaminating process can not but be rapid, and wherever ample provision is not made for rapidly changing the air of the room a dangerous condition of affairs is sure to exist. Bacteria of many forms, and spores of fungi, are also found in the air, and all these organisms are known to thrive in the organic impurities found in the air.’ ❂ Chapter IV: Examination Of The Air (p.33) ❦ On measuring CO₂ levels as a proxy to establishing content of (infectious) re-breathed air: ‘A complete analysis of impure air comprehends the quantitative and qualitative tests for carbonic [sic] dioxide, free ammonia, and other nitrogenous matter, oxidizable matters, nitrous and nitric acids, and hydrogen sulphide; but for ordinary practical purposes the determination of the CO₂ is by far the most important, and is ordinarily the only one which need be made. While the poisonous qualities of the air are not wholly due to the presence of the CO₂ per se, the amount of this gas found to be present is, in air made impure by respiration, generally a good measure for other impurities to which the poisonous quality is principally due. Owing to this fact, a careful test for the amount of CO₂ contained in a given atmosphere is generally the only one which need be made where air is tested merely to determine its respiratory purity.’ ❂ 📖 (Accessed 10 Apr 2024 ~ D. Appleton & Company / Google Books) The Ventilation and Warming of School Buildings ➤ ❂ My thanks to Maarten De Cock for alerting me to this gem of a book. ➲

❦ SARS-CoV-2 – the virus that causes Covid-19 – is airborne . In May 2021, the WHO officially recognised that SARS-CoV-2 is airborne via microscopic aerosols – meaning that the virus is transmissible through the air at both long and short range .

‘ Reinfection , which is now the dominant type of SARS-CoV-2 infection , is not inconsequential ; it can trigger de novo Long Covid or exacerbate its severity . Each reinfection contributes additional risk of Long Covid: cumulatively , two infections yield a higher risk of Long Covid than one infection , and three infections yield a higher risk than two infections .’

❦ This study confirms everything that I have seen in the microscope over the last few years. The authors of the study use a technique called dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), an imaging technique that can measure the density, integrity, and leakiness of tissue vasculature. Comparing all individuals with previous COVID infection to unaffected controls revealed decreased general brain volume in patients with brain fog along with significantly reduced cerebral white matter volume in both hemispheres in the recovered and brain fog cohorts . Covid-19 induces brain volume loss and leaky blood-brain barrier in some patients. How can this be more clear? © 2024 Danielle Beckman. ➲ ❂ 📖 (22 Feb 2024 ~ Nature: Neuroscience) Blood–brain barrier disruption and sustained systemic inflammation in individuals with long COVID-associated cognitive impairment ➤ 📖 (22 Feb 2024 ~ Nature: Neuroscience) Leaky blood–brain barrier in long-COVID-associated brain fog ➤ ➲ Layperson overview: 📖 (February 2024 ~ Genetic Engineering and Biotechnology News) Leaky Blood Vessels in the Brain Linked to Brain Fog in Long COVID Patients ➤ Related: 📖 (7 Feb 2022 ~ Nature: Cardiovascular Research) Blood–brain barrier link to human cognitive impairment and Alzheimer’s disease ➤ ❂ © 2024 Nature .

‘The very first canon of nursing... the first essential to the patient... is this: to keep the air he breathes as pure as the external air, without chilling him .’ ❂ Notes on Nursing (1860 edition) By Florence Nightingale First Published 1859. Revised edition reprinted in 1860 by Harrison of Pall Mall Accessed 19 Feb 2024 ❦ Chapter I – Ventilation and Warming ‘The very first canon of nursing, the first and the last thing upon which a nurse’s attention must be fixed, the first essential to the patient, without which all the rest you can do for him is as nothing, with which I had almost said you may leave all the rest alone, is this: TO KEEP THE AIR HE BREATHES AS PURE AS THE EXTERNAL AIR, WITHOUT CHILLING HIM. Yet what is so little attended to? Even where it is thought of at all, the most extraordinary misconceptions reign about it. Even in admitting air into the patient’s room or ward, few people ever think where that air comes from. It may come from a corridor into which other wards are ventilated, from a hall, always unaired, always full of the fumes of gas, dinner, of various kinds of mustiness; from an underground kitchen, sink, wash-house, water-closet, or even, as I myself have had sorrowful experience, from open sewers loaded with filth; and with this the patient’s room or ward is aired, as it is called – poisoned, it should rather be said. Always air from the air without, and that, too, through those windows, through which the air comes freshest. From a closed court, especially if the wind do not blow that way, air may come as stagnant as any from a hall or corridor. I know an intelligent humane house surgeon who makes a practice of keeping the ward windows open. The physicians and surgeons invariably close them while going their rounds; and the house surgeon, very properly, as invariably opens them whenever the doctors have turned their backs. I have known a medical officer keep his ward windows hermetically closed, thus exposing the sick to all the dangers of an infected atmosphere, because he was afraid that, by admitting fresh air, the temperature of the ward would be too much lowered. This is a destructive fallacy. To attempt to keep a ward warm at the expense of making the sick repeatedly breathe their own hot, humid, putrescing atmosphere is a certain way to delay recovery or to destroy life.’ ❂ ‘I have known cases of hospital pyæmia quite as severe in handsome private houses as in any of the worst hospitals, and from the same cause, viz., foul air. Yet nobody learnt the lesson. Nobody learnt anything at all from it.’ ❂ ✪ C-19: On schools ‘Of all places, public or private schools, where a number of children or young persons sleep in the same dormitory * , require this test of freshness to be constantly applied.’ * [ C-19 Note: You might substitute ‘sleep’ and ‘dormitory’ with ‘study’ and ‘classroom’ in this section.] ‘If it be hazardous for two children to sleep together in an unventilated bedroom, it is more than doubly so to have four, and much more than trebly so to have six under the same circumstances. People rarely remember this; yet, if parents were as solicitous about the air of school bedrooms as they are about the food the children are to eat, and the kind of education they are to receive, at school, depend upon it due attention would be bestowed on this vitally important matter, and they would cease to have their children sent home either ill, or because scarlet fever or some other “current contagion” had broken out in the school. There are schools where attention is paid to these things, and where “children’s epidemics” are unknown.’ ❂ ✪ C-19: Offices, shops, factories, and other workplaces ‘How much sickness, death, and misery are produced by the present state of many factories, warehouses, workshops, and workrooms!’ ‘How much sickness, death, and misery are produced by the present state of many factories, warehouses, workshops, and workrooms! The places where poor dressmakers, tailors, letter-press printers, and other similar trades have to work for their living, are generally in a worse sanitary condition than any other portion of our worst towns. Many of these places of work were never constructed for such an object. They are badly adapted garrets, sitting-rooms, or bedrooms, generally of an inferior class of house. No attention is paid to cubic space or ventilation. The poor workers are crowded on the floor to a greater extent than occurs with any other kind of over-crowding. The constant breathing of foul air, saturated with moisture, and the action of such air upon the skin renders the inmates peculiarly susceptible of the impression of cold, which is an index indeed of the danger of pulmonary disease to which they are exposed. The result is, that they make bad worse, by over-heating the air and closing up every cranny through which ventilation could be obtained. In such places, and under such circumstances of constrained posture, want of exercise, hurried and insufficient meals, long exhausting labour and foul air – is it wonderful that a great majority of them die early of chest disease, generally of consumption? Intemperance is a common evil of these workshops. The men can only complete their work under the influence of stimulants, which help to undermine their health and destroy their morals, while hurrying them to premature graves. Employers rarely consider these things. Healthy workrooms are no part of the bond into which they enter with their work-people. They pay their money, which they reckon their part of the bargain. And for this wage the workman or workwoman has to give work, health, and life. Do men and women who employ fashionable tailors and milliners ever think of these things? And yet the master is no gainer. His goods are spoiled by foul air and gas fumes, his own health and that of his family suffers, and his work is not so well done as it would be, were his people in health. And the time will come when it will be found cheaper to supply shops, warehouses, and work-rooms with pure air than with foul air.’ ‘And the time will come when it will be found cheaper to supply shops, warehouses, and work-rooms with pure air than with foul air.’ ❂ ✪ C-19: On ‘air-tests’, and measuring CO₂ as a proxy for estimating prevalence of airborne disease indoors ‘Dr. Angus Smith’s air-test, if it could be made of simple application, would be invaluable to use in every sleeping and sick room. Just as without the use of a thermometer no nurse should ever put a patient into a bath, so, if this air-test were made in some equally simple form, should no nurse, or mother, or superintendent, be without it in any ward, nursery, or sleeping-room. But to be used, the air-test must be made as simple a little instrument as the thermometer, and both should be self-registering. ‘...the air-test must be made as simple a little instrument as the thermometer, and both should be self-registering.’ The senses of nurses and mothers become so dulled to foul air that they are perfectly unconscious of what an atmosphere they have let their children, patients, or charges sleep in. But if the tell-tale air-test were to exhibit in the morning, both to nurses and patient and to the superior officer going round, what the atmosphere has been during the night, I question if any greater security could be afforded against a recurrence of the misdemeanour.’ ❂ ✪ C-19: ... And back to the school-room, testing its air, and combatting airborne pathogens ‘And, oh! the crowded national school! where so many children’s epidemics have their origin; and the crowded, unventilated work-room, which sends so many consumptive men and women to the grave; what a tale its air-test would tell! We should have parents saying, and saying rightly, “I will not send my child to that school. I will not trust my son or my daughter in that tailor’s or milliner’s workshop, the air-test stands at ‘Horrid.’” ‘We should have parents saying, and saying rightly, “I will not send my child to that school... the air-test stands at Horrid .”’ And the dormitories of our great boarding schools! Scarlet fever would be no more ascribed to contagion but to its right cause, the air-test standing at “Foul.” We should hear no longer of “mysterious dispensations,” nor of “plague and pestilence” being “in God’s hands,” when, so far as we know, He has put them into our own. The little air-test would both betray the cause of these “mysterious pestilences,” and call upon us to remedy it.’ ❂ ❦ Chapter II – Health of Houses ‘There are five essential points in securing the health of houses:– Pure air. Pure water. Efficient drainage. Cleanliness. Light. Without these, no house can be healthy. And it will be unhealthy just in proportion as they are deficient. To have pure air, your house must be so constructed as that the outer atmosphere shall find its way with ease to every corner of it. ‘To have pure air, your house must be so constructed as that the outer atmosphere shall find its way with ease to every corner of it.’ House architects hardly ever consider this. The object in building a house is to obtain the largest interest for the money, not to save doctor’s bills to the tenants. But, if tenants should ever become so wise as to refuse to occupy unhealthily constructed houses, and if Insurance Companies should ever come to understand their interest so thoroughly as to pay a Sanitary Surveyor to look after the houses where their clients live, speculative architects would speedily be brought to their senses. As it is, they build what pays best. And there are always people foolish enough to take the houses they build. And if in the course of time the families die off, as is so often the case, nobody ever thinks of blaming any but Providence for the result. Ill-informed medical men aid in sustaining the delusion, by laying the blame on “current contagions”. Badly constructed houses do for the healthy what badly constructed hospitals do for the sick.’ ‘Badly constructed houses do for the healthy what badly constructed hospitals do for the sick.’ ❂ ❦ Conclusion ‘The whole of the preceding remarks apply even more to children and to puerperal women than to patients in general. They also apply to the nursing of surgical, quite as much as to that of medical cases. Indeed, if it be possible, cases of external injury require such care even more than sick. In surgical wards, one duty of every nurse certainly is prevention. Fever, or hospital gangrene, or pyæmia, or purulent discharge of some kind may else supervene. If she allows her ward to become filled with the peculiar close fœtid smell, so apt to be produced among surgical cases, especially where there is great suppuration and discharge, she may see a vigorous patient in the prime of life gradually sink and die where, according to all human probability, he ought to have recovered. The surgical nurse must be ever on the watch, ever on her guard, against want of cleanliness, foul air, want of light, and of warmth.’ ‘In surgical wards, one duty of every nurse certainly is prevention.’ ❂ 📖 (Accessed 19 Feb 2024 ~ Original text copied from FiftyWordsForSnow.com) Notes on Nursing (1860) ➤ 📖 (Accessed 19 Feb 2024 ~ Original scanned pages from Google Books) Notes on Nursing (1860) ➤ ❂

❦ LitCovid is the most comprehensive online resource on SARS-CoV-2 / COVID-19, providing access to 417,800+ relevant articles on PubMed. The library of scientific articles is updated daily, and categorised by different research topics (e.g. transmission), as well as geographic locations. ➲ Date accessed: 18 Feb 2024 . ❂ ❦ Useful Categories ✪ Transmission ➤ Characteristics and modes of SARS-CoV-2 transmission. ✪ Prevention ➤ Prevention, control, response and management strategies. ✪ Long Covid ➤ Post-COVID-19 Conditions/Complications (PCC) / Post-Acute Sequelae of COVID-19 (PASC). ✪ Case Reports ➤ Descriptions of specific patient cases. ✪ Treatments ➤ Treatment strategies, therapeutic procedures, and vaccine development. ✪ Forecasting ➤ Modelling, and estimating the trend of SARS-CoV-2 spread. ❂ ➲ LitCovid Online Library ➤ © 2024 National Institutes for Health (NIH) / National Center for Biotechnology Information (NCBI) / U.S. National Library of Medicine (NLM USA).

❦ Mitigation = ‘Lessening the force or intensity of something unpleasant; the act of making a condition or consequence less severe.’ 1. Clean indoor air . The priority should be air filters in schools and hospitals . New ventilation and air filtration standards for all public spaces . Grants made available to businesses to upgrade ventilation and air filtration . 2. FFP2/3 [N95/N99] respirators (masks) in all healthcare settings . 3. Free Covid vaccines available to everyone. 4. Wider access to Covid anti-viral treatments . 5. Free LFT/PCR testing . 6. Improved Covid surveillance , including wastewater monitoring and Long Covid prevalence . 7. Paid sick-leave , so that people don’t go to work when ill. 8. Respirators (masks) on public transport , including flights . 9. Better support and treatments for Long Covid patients . ... and last, but by no means least: 10. A public education campaign on the long-term risks of Covid – and why people should do more to protect themselves. ❦ Addendum : Allocate adequate research funding for a sterilising vaccine as well as treatments/cure for Long Covid . ❂ © 2024 Cat in the Hat . ➲

❦ ‘The occurrences of respiratory disorders among patients who survived for 30 days after the COVID-19 diagnosis continued to rise consistently, including asthma , bronchiectasis , COPD , ILD , PVD * , and lung cancer . * COPD = Chronic obstructive pulmonary disease . ILD = Interstitial lung disease . PVD = Peripheral vascular disease . With the severity of the acute phase of COVID-19, the risk of all respiratory diseases increases progressively. Besides, during the 24-months follow-up, we observed an increasing trend in the risks of asthma and bronchiectasis over time, which indicates that long-term monitoring and meticulous follow-up of these patients is essential. These findings contribute to a more complete understanding of the impact of COVID-19 on the respiratory system and highlight the importance of prevention and early intervention of these respiratory sequelae of COVID-19. In this study, several key findings have been further identified. Firstly, our research demonstrates a significant association between COVID-19 and an increased long-term risk of developing various respiratory diseases. Secondly, we found that the risk of respiratory disease increases with severity in patients with COVID-19, indicating that it is necessary to pay attention to respiratory COVID-19 sequelae in patients, especially those hospitalized during the acute stage of infection. This is consistent with the findings of Lam et al., who found that the risk of some respiratory diseases (including chronic pulmonary disease, acute respiratory distress syndrome and ILD) increased with the severity of COVID-19. Notably, however, our study found that asthma and COPD remained evident even in the non-hospitalized population. This emphasizes that even in cases of mild COVID-19, the healthcare system should remain vigilant. Thirdly, we investigated differences in risk across time periods, as well as the long-term effects of COVID-19 on respiratory disease. During the 2-years follow-up period, the risks of COPD, ILD, PVD and lung cancer decreased, while risks of asthma and bronchiectasis increased. Fourthly, our study showed a significant increase of the long-term risk of developing asthma, COPD, ILD, and lung cancer diseases among individuals who suffered SARS-CoV-2 reinfection. This finding emphasizes the importance of preventing reinfection of COVID-19 in order to protect public health and reduce the potential burden of SARS-CoV-2 reinfection. Interestingly, vaccination appears to have a potentially worsening effect on asthma morbidity compared with other outcomes. This observation aligns with some previous studies that have suggested a possible induction of asthma onset or exacerbation by COVID-19 vaccination. It suggests that more care may be necessary for patients with asthma on taking the COVID vaccines. The underlying mechanisms associated with COVID and respiratory outcomes are not fully understood, but several hypotheses have been proposed. First, SARS-CoV-2 can persist in tissues (including the respiratory tract), as well as the circulating system for an extended period of time after the initial infection. This prolonged presence of the virus could directly contribute to long-term damage of the respiratory tissues, consequently leading to the development of various respiratory diseases. Second, it has been observed that SARS-CoV-2 infection can lead to prolonged immunological dysfunctions, including highly activated innate immune cells, a deficiency in naive T and B cells, and increased expression of interferons and other pro-inflammatory cytokines. These immune system abnormalities are closely associated with common chronic respiratory diseases – asthma, bronchiectasis, COPD, as well as the development of lung cancer. Next, SARS-CoV-2 itself has been shown to drive cross-reactive antibody responses, and a range of autoantibodies were found in patients with COVID-19. In conclusion, our research adds to the existing knowledge regarding the effects of COVID-19 on the respiratory system. Specifically, it shows that the risk of respiratory illness increases with the severity of infection and reinfection. Our findings emphasize the importance of providing extended care and attention to patients previously infected with SARS-CoV-2.’ ❂ 📖 (17 Feb 2024 ~ The Lancet: eClinical Medicine) Long-term risks of respiratory diseases in patients infected with SARS-CoV-2: a longitudinal, population-based cohort study ➤ © 2024 The Lancet: eClinical Medicine .

❦ Chronic disease is like the perfect medical crime. The cause is usually long gone by the time the disease manifests, and nobody links the two until it’s much too late for most. ❂ © 2024 Henry Madison . ➲

❦ It’s really not in the interest of the virus to kill us quickly. That’s why it has mutated to immune escape. That way it enters silently, and then eats you slowly whilst you’re still a spreading vector. Refrigerator trucks are long gone. That’s all the political class wanted. The unseen costs of CVD [cardiovascular disease] , DM [diabetes mellitus] , and both dementia and Parkinson’s Disease are the train coming down the tunnel. The economists are catching up. The actuaries are already there. Politicians and most people? Not yet... ❂ © 2024 Dr. David Joffe, PhD, FRACP / Respiratory Physician ➲ .

❦ Genomic epidemiology of SARS-CoV-2 with subsampling focused globally since pandemic start. ➲ Built with nextstrain/ncov . Maintained by the Nextstrain team . Enabled by data from GISAID . ➲ Data updated: 21 Jan 2024. ➲ Date accessed: 21 Jan 2024. ❂ © 2024 NextStrain.org ➲

❦ “Every single case in which a person with COVID-19 infects another person in a healthcare setting – patient, relative, or hospital staff member – is a significant failure of hospital procedures. Every single instance .” ❂ © 2024 Professor Steve Robson MPH MD PhD ~ President, Australian Medical Association (AMA) . ➲

❦ Mike Honey’s Variant Visualiser (COVID-19 Genomic Sequence Analysis). The region of ‘Oceania/Australia’ is set by default, as the visualiser was created by Mike Honey , a Data Visualisation and Data Integration specialist in Melbourne, Australia. ➲ Choose your country by clicking on the ‘ Continent, Country, Location ’ dropdown menu in the top-right-hand corner . The variant visualiser is free to use, and is automatically updated every time you open the link. ❂ © 2024 Mike Honey .

❦ ‘Although some studies have shown neuroimaging and neuropsychological alterations in post-COVID-19 patients, fewer combined neuroimaging and neuropsychology evaluations of individuals who presented a mild acute infection. Here we investigated cognitive dysfunction and brain changes in a group of mildly infected individuals. We conducted a cross-sectional study of 97 consecutive subjects ( median age of 41 years ) without current or history of psychiatric symptoms (including anxiety and depression) after a mild infection , with a median of 79 days (and mean of 97 days ) after diagnosis of COVID-19. We performed semi-structured interviews, neurological examinations, 3T-MRI scans, and neuropsychological assessments. The patients reported memory loss ( 36% ), fatigue ( 31% ) and headache ( 29% ). The quantitative analyses confirmed symptoms of fatigue ( 83% of participants), excessive somnolence ( 35% ), impaired phonemic verbal fluency ( 21% ), impaired verbal categorical fluency ( 13% ) and impaired logical memory immediate recall ( 16% ). Our group… presented higher rates of impairments in processing speed ( 11.7% in FDT- Reading and 10% in FDT- Counting ). The white matter (WM) analyses with DTI * revealed higher axial diffusivity values in post-infected patients compared to controls. * Diffusion tensor imaging tractography , or DTI tractography, is an MRI (magnetic resonance imaging) technique most commonly used to provide imaging of the brain. Our results suggest persistent cognitive impairment and subtle white matter abnormalities in individuals mildly infected , without anxiety or depression symptoms. One intriguing fact is that we observed a high proportion of low average performance in our sample of patients (which has a high average level of education ), including immediate and late verbal episodic memory, phonological and semantic verbal fluency, immediate visuospatial episodic memory, processing speed, and inhibitory control . Although most subjects did not present significant impaired scores compared with the normative data, we speculate that the low average performance affecting different domains may result in a negative impact in everyday life , especially in individuals with high levels of education and cognitive demands .’ ❂ ❦ Note how these findings might negatively affect daily activities that demand sustained cognitive attention and fast reaction times – such as driving a car or motorbike, or piloting a plane. Consider air-traffic control. Consider the impact on healthcare workers whose occupations combine long periods of intense concentration with a need for critical precision. ❂ 📖 (19 Jan 2024 ~ Nature: Scientific Reports) Microstructural brain abnormalities, fatigue, and cognitive dysfunction after mild COVID-19 ➤ © 2024 Nature .

‘Clinical evidence suggests that SARS-CoV-2 may lead to hypocalcemia, altered bone turnover markers, and a high prevalence of vertebral fractures.’

❦ We cannot individually assess the risk of infection from poor indoor air quality. Just as we cannot individually assess food safety in restaurants, or fire safety in cinemas, or aviation safety on flights. These are in the control of others, and are regulated for our health and safety. ❂ © 2024 Orla Hegarty . ➲

❦ ‘Acute infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cause a respiratory illness that can be associated with systemic immune cell activation and inflammation , widespread multi-organ dysfunction , and thrombosis . Not everyone fully recovers from COVID-19, leading to Long Covid, the treatment of which is a major unmet clinical need. Long Covid can affect people of all ages , follows severe as well as mild disease , and involves multiple organs . Patients with Long Covid display signs of immune dysfunction and exhaustion , persistent immune cell activation , and autoimmune antibody production , which are also pathological features of acute COVID-19. The complement system is crucial for innate immune defense by effecting lytic destruction of invading micro-organisms, but when uncontrolled, it causes cell and vascular damage . The complement cascade is activated by antigen–antibody complexes in the classical pathways or in the lectin pathway by multimeric proteins (lectins) that recognize specific carbohydrate structures, which are also found on the SARS-CoV-2 spike protein that facilitates host cell entry. Both pathways may contribute to the pronounced complement activation in acute COVID-19. Long Covid symptoms include a postexertional exhaustion reminiscent of other post-viral illnesses , such as myalgic encephalomyelitis ( ME ) – chronic fatigue syndrome ( MECFS ) with suspected latent viral reactivation . Antibody titer changes in Long Covid patients indicate an association of fatigue with reactivation of latent Epstein-Barr virus ( EBV ) infections , and Cervia-Hasler et al found that the severity of Long Covid symptoms is associated with cytomegalovirus ( CMV ) reactivation . A better understanding of the connections between viral reactivation, persistent interferon signaling, and autoimmune pathologies promises to yield new insights into the thromboinflammation associated with Long Covid. Although therapeutic interventions with coagulation and complement inhibitors in acute COVID-19 produced mixed results, the pathological features specific for Long Covid suggest potential interventions for clinical testing. Microclots are also observed in ME-CFS patients , indicating crucial interactions between complement, vWF, and coagulation-mediated fibrin formation in post-viral syndromes. A better definition of these interactions in preclinical and clinical settings will be crucial for the translation of new therapeutic concepts in chronic thromboinflammatory diseases .’ ❂ 📖 (18 Jan 2024 ~ Science) Immune damage in Long Covid ➤ © 2024 Wolfram Ruf / Science .

“I would argue that COVID-19 is not a disease of the lungs at all.  It seems most likely that it is what we call a vascular and neurologic infection, affecting both nerve endings and our cardiovascular system.”

❦ I met a nice lady – a ward patient – yesterday who, seeing my respirator [high-filtration mask] , promptly put on her surgical mask. So instead of diving straight in to asking what was most concerning her and how I could help, I opened up a bit about infection control in hospitals. I explained how, because of a lack of respirators, March 2020 saw NHS leaders downgrade PPE for all non-ICU staff. ❂ PPE : Personal Protective Equipment. I then reminded her of the amazing DHSC 2020 and 2021 campaigns on airborne transmission of SARS2 (the green-and-black smoke ones) – and I had to point out that every IPC Lead Nurse had since had to switch off their brain and forget what they knew – and while at work, to only protect ICU staff. ❂ DHSC : Department of Health and Social Care (UK). ❂ IPC : Infection Prevention and Control. I explained that the individuals responsible for the original IPC downgrade were now authors of the national manual on IPC (NIPCM), which sets the standard for infection control in hospitals, and this manual states that airborne transmission is ‘not a thing’ for SARS2 (AGP only). ❂ NIPCM : The UK’s National Infection Prevention and Control Manual. ❂ AGP : Aerosol-Generating Procedure, ie. intubation. So hospitals are destined to be unsafe spaces thanks to the NIPCM, and the surgical mask that she was wearing was OK (ish) to help protect me – but did very little to reduce her risk of SARS2 inhalation. However, she was in a single room (an extra, and not meant as a ward-bed space – but you know, >100% occupancy forever means that you need to use your imagination) – and she already had the window open. She was appalled at what healthcare workers were being put through. She was appalled at the on-going lies. She was appalled at the possible level of harm to patients and staff from such lies. She then went on to tell me how a weekend visitor of hers had just tested positive for Covid. She was worried that they had hugged and chatted, and that she might have got infected. She’s a switched on lady, too. Lives with a medic who has the windows open all the time (“It’s freezing at home”). So I explained about the CleanAirStars.com site. About HEPA filtration being a low energy and low-cost way to remove all airborne pathogens, and to make home a safer place for... • Covid • Flu • RSV • Norovirus • Fungi Etc., etc. The list goes on and on. — “Wow, that’s like magic!” We had a very nice chat. And then we talked about her heart. I just wish I could have this same conversation with each and every NHS CEO and IPC Lead Nurse. I’d ask some questions. I’d want to know why they aren’t protecting staff as they should. I’d want to know why they aren’t protecting patients as they should. I’d want them to know that they are in breach of UK legislation. And I’d want to look them in the eye and ask them to show compassion to the powerless: to staff, and patients. Help us please. Do whatever you can to counter the lies, and to help protect the NHS. Thank-you. ❂ © 2024 Dr. David Tomlinson, NHS Consultant Cardiologist ➲ .

❦ ‘Alzheimer’s disease (AD) is acknowledged by the World Health Organisation (WHO) as a global public health concern. AD is the primary cause of dementia and accounts for 50–70% of cases. SARS-CoV-2 can damage the peripheral and the central nervous system (CNS) through both direct and indirect pathways, potentially leaving COVID-19 patients at higher risks for neurological difficulties, including depression, Parkinson’s disease, AD, etc., after recovering from severe symptoms. Patients who recovered from severe COVID-19 infection are more likely to acquire stable neuropsychiatric and neurocognitive conditions like depression, obsessive-compulsive disorder, psychosis, Parkinson’s disease, and Alzheimer’s disease. SARS-CoV-2 infection causes immune system dysfunction, which can lead to suppression of neurogenesis, synaptic damage, and neuronal death, all of which are associated with the aetiology of Alzheimer’s disease. Severe systemic inflammation caused by SARS-CoV-2 is predicted to have long-term negative consequences, such as cognitive impairment. Research has demonstrated that SARS-CoV-2-infected AD patients had a higher mortality rate. In a study from the Department of Neuroscience at the University of Madrid, 204 participants with Frontotemporal Dementia (FTD) and Alzheimer’s disease (AD) were enrolled. According to the study, 15.2% of these individuals had COVID-19 infection, and sadly, 41.9% of those who had the virus died as a result of their illness. COVID-19 causes a secondary effect on underlying brain pathologies, as SARS-CoV-2 has been shown to trigger or accelerate neurodegeneration processes that possibly explain long-term neurodegenerative effects in the elderly population. In response to the impact of COVID-19 in 2020, governments worldwide acted promptly by implementing various public health measures. During this period, people with cognitive impairments such as dementia or AD may have experienced greater stress and anxiety due to sudden changes in the environment and people’s behaviour. It is also significantly harder for AD patients to comprehend and execute defensive measures such as wearing face masks and sanitising frequently. ❂ COVID-19 has generated a worldwide outbreak, resulting in a slew of issues for humans, particularly those suffering from Alzheimer’s disease. Its ability to invade the central nervous system through the hematogenous and neural routes, besides attacking the respiratory system, has the potential to worsen cognitive decline in Alzheimer’s disease patients. The severity of this issue must be highlighted.’ ❂ 📖 (8 Jan 2024 ~ Frontiers in Aging Neuroscience) Unravelling the connection between COVID-19 and Alzheimer’s disease: a comprehensive review ➤ © 2024 Shajahan et al / Frontiers in Aging Neuroscience .

❦ Q . Why is it important for me to know if I have a COVID-19 infection? ❦ A . If you don’t recover well, it can help your doctor to know if you’ve had a COVID-19 infection – so that they can more effectively treat any of your on-going symptoms. It also helps you to be conscious of the fact that contact with other people might hurt, permanently damage, or kill them.

Post-exertional malaise (PEM) is a marked physical or mental fatigue and deterioration of symptoms occurring after physical , cognitive , social or emotional exertion that would have been tolerated previously. Symptoms typically worsen 12 to 48 hours after such activities , and can last for days , weeks or months , making it difficult to manage or predict. PEM is a hallmark symptom of myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS), and is commonly reported by people with Post-COVID-19 Syndrome (PCS/‘Long Covid’). PEM can be mitigated by activity management , or ‘ pacing ’.

❦ Person puts hand in flame. Gets burnt. Knows fire burns flesh. Has a fear of getting burnt in the future, because fire and flesh create undesirable pain. Lives in a permanent state of fear of fire for rest of life? No. Becomes cautious of fire, and takes precautions to not be burnt again. If anybody accuses you of ‘living in fear’ for taking precautions to avoid catching SARS-CoV-2 (Covid-19) again and again, know that you are, in fact, ‘living with sensible caution’ – as you know that the headaches and heart attacks and strokes and plaque build-up in arteries and the killing of one’s own parents and the reduction of your children’s IQ and your daily fatigue and your memory disorders and immune dysregulation and your new-onset susceptibility to other opportunistic viral, bacterial and fungal infections, and your high blood pressure, and your aggressive, new-onset or recurrence of cancer and the rapid, aggressive, new-onset dementia – are all things you should rightly be afraid of. For yourself, and for other people. But SARS-2 is clever. You often only feel the burn weeks or months later, and you don’t make the connection between the time you stuck your hand in a fire and the now-septic wound that has worked its way into the gristle of your fingers. SARS-2 isn’t stupid, you know, and it has had four years of mutating repeatedly inside several billion humans and animals to hone its game while we sit on the lawn and watch our house burn down. ❂ © 2023 C19.Life .

❦ Ms Amanda Pritchard Chief Executive Officer NHS England Sent via email 22 December 2023 Dear Ms Pritchard, Re: Need for revisions to the IPC guidance to protect healthcare workers from COVID-19 Recently, we have been hearing increasing concerns from across our respective memberships about the protection of healthcare workers and patients from COVID-19 , particularly in light of the rise in cases, hospitalisations and deaths that occurred in September and October [2023] . While it was positive to see a reduction in cases and hospitalisations in November which hopefully reflected a reduction in prevalence as well as the effect of the autumn booster programme, we are starting to see early signs that hospitalisations and cases are starting to rise again. There is no room for complacency, particularly as we deal with winter with an NHS under serious strain. In any case, suppressing the virus remains crucial to reduce the risk of new variants of concern . Moreover, the consequences of infection for some individuals remain serious. We have heard from a range of multidisciplinary clinicians from across primary and secondary care express concern about the lack of availability of even the most basic protections in many settings when they are treating patients with confirmed or suspected COVID-19 . Additionally, the BMA’s Patient Liaison Group has shared information about vulnerable patients not attending healthcare settings due to the fear of a possible COVID-19 infection . These are patients, who remain more susceptible to severe disease from COVID-19 and those for whom vaccines are less effective. As we have routinely highlighted, we believe that the existing Infection Prevention Control ( IPC ) Manual for England , and the specific IPC guidance for COVID-19 which preceded it, have contributed to the lack of protection many of our members experience. The manual does appear to recognise that COVID-19 is airborne . It states that Respiratory Protective Equipment ( RPE ), (i.e. a ( FFP ) respirator ) must be considered when treating a patient with a virus spread wholly or partly by the airborne route (2.4). However, it then makes an unclear distinction between viruses spread wholly or partly by the airborne route , and those spread wholly or partly by the airborne or droplet route where RPE is only recommended for so called “Aerosol Generating Procedures” (AGPs) – an outdated concept based on very poor evidence . Specifically , in Appendix 11, it states that a fluid resistant surgical mask ( FRSM ) is adequate protection for the routine care of COVID-19 positive patients (appendix 11), directly contradicting the statement in 2.4. It also seems very odd to make a distinction between viruses that spread only via the airborne route and those spreading via the airborne or droplet route; staff need protection from an airborne virus in both cases , in one they also need to take droplet-based precautions. The HSE’s own research from 2008 confirms a lack of respiratory protection from a FRSM . It is accepted that COVID-19 can be and is spread by the airborne route . The recent evidence given at the UK COVID-19 Inquiry clearly shows that aerosol transmission is a significant , and almost certainly the dominant, route of transmission for COVID-19 . The current guidance is therefore, at the very least, confusing and, at the worst , is recommending inadequate protection for healthcare workers treating COVID-19 patients . This continues to put them and their patients at risk of infection and, in some cases, Long Covid. We are concerned that there has been a lack of stakeholder engagement in recent months to inform updates the IPC Manual. The latest update on 25 October 2023 does not change the recommended PPE for routine care of a patient with COVID-19, although does include a new footnote seven which concerns patients with undiagnosed respiratory illness where coughing and sneezing are significant features but does not mention COVID-19 or provide guidance on recommended PPE or RPE. Stakeholders, including the signatories to this letter are seeking clarity from you about how we can engage with this process to help inform future revisions of the manual and ensure the guidance is clear and recommends adequate protection for healthcare workers. Employers ultimately have the responsibility for the safety of their workforce , under Health and Safety Law , and the IPC Manual for England references the need for risk assessments and the need to follow the hierarchy of controls. Ensuring the protection , so far as reasonably practicable, of staff who are vulnerable through exposure to the virus and any staff or patients who are individually susceptible and at risk of serious illness if they catch COVID-19 , remains a paramount legal obligation . However, the IPC guidance issued by UKHSA is mandatory in all NHS settings and settings where NHS services are provided. This makes it makes it very difficult for NHS Trusts to reconcile the confusing IPC guidance with their statutory duties as employers under health and safety legislation to provide HSE-approved RPE for protection against airborne hazards . This is especially the case as the HSE has opted not to produce its own guidance on the subject. As we deal with winter, when pressure in the NHS intensifies alongside rising flu and other seasonal respiratory viruses, as well as COVID-19, ensuring there are enough staff across the NHS is more important than ever. COVID-19 is likely to still cause significant staff absence , particularly if cases continue to rise in the coming weeks and months. Providing clear and adequate IPC guidance , including on the need for RPE and adequate ventilation , will help protect healthcare workers and patients and reduce staff absence this winter. Providing staff with adequate protection will also better protect patients and will help reassure vulnerable patients they can safely access healthcare . We would appreciate your reassurance that our concerns will be addressed and the relevant IPC guidance will be urgently updated to reflect this, as well as routinely reviewed. We are of course willing to work with your colleagues and the Chief Nursing Officer on IPC guidance. Yours sincerely, Professor Phil Banfield. BMA, Chair of Council. Dr Barry Jones. Chair of Covid Airborne Protection Alliance (CAPA). ❂ 📖 (22 Dec 2023 ~ The British Medical Association & Covid Airborne Protection Alliance) Need for revisions to the IPC guidance to protect healthcare workers from COVID-19 ➤

❦ We’ve contacted chief nursing officers in all four UK countries and the UKHSA to find out what action will be taken in response to WHO’s statement on a new COVID-19 variant of interest. The RCN is asking for a revision to current guidelines , to introduce universal implementation of the two measures advised by the World Health Organization (WHO) to help protect healthcare staff against COVID-19. Earlier this week, in light of the new COVID JN.1 variant, WHO advised healthcare workers and health facilities to: implement universal masking in health facilities , as well as appropriate masking , respirators and other personal protective equipment for health workers caring for suspected and confirmed COVID-19 patients ; improve ventilation in health facilities . The existing national infection prevention and control manuals don’t require standardised masking for COVID-19, and decisions on respiratory protective equipment are left to local risk assessments. This is now inconsistent with WHO’s latest advice . We also have concerns about the adequacy of ventilation in general ward and outpatient areas within hospital buildings and believe that action must be taken to assess and improve this. Although evidence suggests that the global public health risks from the new variant are low, WHO has warned that onset of winter could increase the burden of respiratory infections in the Northern hemisphere. This comes when there are already unsustainable pressures on the health service. Figures show that there has been a rise in COVID-19 cases and hospitalisations , and the RCN argues that without proper protections , ill health could continue to rise in nursing staff and impact their ability to deliver safe and effective patient care . WHO has advised that it is continuously monitoring the evidence and will update the JN.1 risk evaluation as needed. The RCN is urging health care employers to assess the risk posed by COVID-19 and put appropriate safeguards in place for patients and staff . Our COVID-19 workplace risk assessment toolkit aims to help assess and manage the risks associated with respiratory infections such as COVID-19, highlights the duties of nursing staff in specific roles (such as health and safety reps), has advice for employers and leaders, and provides the latest information on risk assessment. ❂ 📖 (21 Dec 2023 ~ Royal College of Nursing / RCN Magazine) COVID JN.1 variant: RCN seeks assurance on new PPE advice ➤ © 2023 Royal College of Nursing (RCN).

❦ ‘Due to its rapidly increasing spread , WHO is classifying the variant JN.1 as a separate variant of interest ( VOI ) from the parent lineage BA.2.86 . It was previously classified as VOI as part of BA.2.86 sublineages. Based on the available evidence, the additional global public health risk posed by JN.1 is currently evaluated as low. Despite this, with the onset of winter in the Northern Hemisphere, JN.1 could increase the burden of respiratory infections in many countries. ➲ Read the risk evaluation: https://www.who.int/activities/tracking-SARS-CoV-2-variants WHO is continuously monitoring the evidence and will update the JN.1 risk evaluation as needed. Current vaccines continue to protect against severe disease and death from JN.1 and other circulating variants of SARS-CoV-2, the virus that causes COVID-19. COVID-19 is not the only respiratory disease circulating. Influenza, RSV and common childhood pneumonia are on the rise. ➲ WHO advises people to take measures to prevent infections and severe disease using all available tools . These include: • Wear a mask when in crowded, enclosed, or poorly ventilated areas, and keep a safe distance from others, as feasible. • Improve ventilation . • Practise respiratory etiquette – covering coughs and sneezes. • Clean your hands regularly. • Stay up-to-date with vaccinations against COVID-19 and influenza, especially if you are at high risk for severe disease. • Stay home if you are sick . • Get tested if you have symptoms, or if you might have been exposed to someone with COVID-19 or influenza. ✻ ➲ For health workers and health facilities , WHO advises : • Universal masking in health facilities , as well as appropriate masking , respirators and other PPE for health workers caring for suspected and confirmed COVID-19 patients . • Improve ventilation in health facilities. Note : Updated 19 Dec 2023 with additional information for health workers and facilities. ’ ❂ 📖 (19 Jan 2023 ~ WHO / World Health Organization) World Health Organization (WHO) Media Advisory for the COVID-19 variant of interest (VOI) JN.1 ➤ © 2023 WHO / World Health Organization. ❦ Date accessed : 11 Jan 2024 .

❦ I am now absolutely convinced that unless we reduce the transmission of Covid-19 through societal non-pharmaceutical interventions (such as cleaning indoor air) and/or the deployment and uptake of second-generation vaccines, attrition of healthcare will reach a tipping point. This tipping point – which may well happen within the next year – will lead to a global decrease in quality of available healthcare services, which in turn will lead to increased morbidity and mortality from all causes. Every government needs to reduce transmission. The denial of this problem will not change the outcome. Policymakers need to understand this. ❂ © 2023 Conor Browne ➲

❦ ‘Al-Aly’s study undertook a comparative analysis of 94 pre-specified health outcomes and found that over 18 months of follow-up, COVID was associated with a “ significantly increased risk ” for 64 of them, or nearly 70% . The disease’s enhanced risk list includes everything from cardiac arrest , stroke , chronic kidney disease , and cognitive impairment to mental health and fatigue , characteristics often associated with long COVID. By comparison, the seasonal flu was associated with increased risk in only 6 of the 94 conditions specified. Further, while COVID increased the risks for almost all the organ systems studied, the flu heightened risk primarily for the pulmonary ( lung ) system . Those findings, Al-Aly says, suggest that “ COVID is really a multi-systemic disease , and flu is more a respiratory virus ”.’ ❂ 📖 (14 Dec 2023 ~ Fortune) COVID-19 v. Flu: A ‘much more serious threat,’ new study into long-term risks concludes ➤ 📖 (14 Dec 2023 ~ The Lancet) Long-term outcomes following hospital admission for COVID-19 versus seasonal influenza: a cohort study ➤ © 2023 Carolyn Barber / Fortune .

❦ “Coughing into one’s sleeve while in shared air is like peeing into one’s swimsuit while in shared water.” ❂ © 2023 Malgorzata Gasperowicz . ➲

❦ Covid Conscious friend’s 40-year-old partying brother gave Covid to their 80-year-old parents. Mother: spent three weeks in the hospital. Father: went into hospice, and died this morning. Forty-year-old brother never went to hospital nor hospice to visit, because “they’re old”, and “what can I do anyway?” He remains maskless. Co-worker who got Covid along with her father at the family reunion... Covid+ father passed out and was found unconscious in his home. Suffered an acute kidney injury; wears a catheter because he can’t ever urinate on his own again; is now in Palliative Care. Co-worker suddenly can’t remember being sick with Covid, nor her father having had Covid and passing out... and is now telling people that he suffered a kidney injury from a slip and a fall. Colleague says on a virtual call: — “Now that the pandemic is over and people have recovered...” She’s been coughing non-stop since July, and can’t figure out “what I’m allergic to”. Friend posts a picture of a box of KN95s [ear-loop FFP2 respirators] that she purchased online with the caption, “Going back to masking. Got them ready. People protect yourself.” Then for the next three weeks posts maskless pictures at a Patti Labelle concert, a wedding, a birthday dinner, a congressional party... I asked her when she’s going to start using the masks that she posted on Facebook. — “When the president mandates us to.” How many people have you talked to about Covid that have had an “Aha moment”, and immediately starts wearing a well-fitted mask and adjusts their behavior long term? The part of the brain that controls emotions like empathy is damaged. The part of the brain that controls cognitive thinking is damaged. Troll behaviour is at an all-time high because people are triggered by you protecting yourself and them. How incredibly bizarre is this behaviour, and almost everyone who is living in this world at this time! ❂ © 2024 Lady Chuan . ➲

❦ As a consequence of their occupation, doctors and other healthcare workers were at higher risk of contracting coronavirus disease 2019 (COVID-19), and more likely to experience severe disease compared to the general population. Post-acute COVID (Long COVID) in UK doctors is a substantial burden. Insufficient respiratory protection could have contributed to occupational disease, with COVID-19 being contracted in the workplace , and resultant post-COVID complications. Although it may be too late to address the perceived determinants of inadequate protection for those already suffering with Long COVID, more investment is needed in rehabilitation and support of those afflicted . ❂ 📖 (11 Dec 2023 ~ Occupational Medicine) Post-acute COVID-19 complications in UK doctors: results of a cross-sectional survey ➤

❦ I’ve often wondered if Covid, a.k.a. SARS-CoV-2, has its own marketing firm. Over the years, we’ve seen annual “campaigns”, if you will. ❊ 2020 : Hide your elderly and disabled! ❦ Covid still kills and disables children , athletes , and working-age adults . ❊ 2021 : Vax and relax! ❦ You can still transmit COVID if vaccinated; the vaccines wane much more quickly than promised; and lack of masking means faster viral evolution via on-going transmission chains. The vaccines only prevent some severe outcomes some of the time . ❊ 2022 : Back to normal, rise and grind! ❦ Forcing a return to offices and schools without proper mitigations in place – such as ventilation , accurate testing and masking – continues to spread Covid. People wonder why “no-one wants to work anymore”. It’s because they’re out sick. ❊ 2023 : Some folks will fall by the wayside. ❦ Anthony Fauci said this in mid-2023. It is intended to normalize continued higher-than-normal rates of death and disability . Please recall that Fauci had to be pushed hard by Larry Kramer to repurpose meds for HIV while he was at the NIH (USA’s National Institutes of Health). ❊ 2024 : There was no way we could have known. ❦ As rates of global disability climb with no long-term antiviral combination therapy approved, the press and the public start to vent frustrations . We absolutely did know – thanks to the basics of exponential functions and mounds of research. ❊ 2025 : Have you considered MAID? ❦ Due to Canadian efforts at successfully delaying care and benefits to living people while pushing medically-assisted intentional death (MAID), Western governments widely adopt the practice as a way of cutting costs. Influencers suggest 65 is “too old”. ❊ 2026 : Your disease, your responsibility. ❦ Government officials assert that it’s your fault if you didn’t wear an N95 [FFP2 respirator] because there was that one time the CDC (USA’s Centers for Disease Control and Prevention) director barely got the word “mask” out on a video in early December 2023. They use it as a reason for blanket denials of benefits . ❊ 2027 : Get adequate rest! ❦ Campaigns designed to educate the public on the benefits of sleep hygiene are ramped up in the face of increased disability. People are encouraged to work fewer hours if they aren’t feeling well, while their employers demand even more. People are tired. ❊ 2028 : Do your homework, kids! ❦ As PISA studies (Programme for International Student Assessment) continue to show global decline in student performance , education officials ignore the cognitive harms of COVID and instead decry cell-phones and “laziness”. Teen suicides increase due to more pressure, but social media is blamed. ❊ I could go on. A different future is possible, but it’s going to require big changes. Ignore the propaganda. Look at the data. Wear an N95 everywhere where people and air mix – and carry extra masks for others if you can. ❂ © 2023 Chalis Montgomery ➲

❦ The reason why most people aren’t taking Covid-19 seriously is because they simply can’t imagine that their public health body would abandon protections and let an incredibly disabling and airborne virus spread wildly. They will be very angry when it becomes clear to them that that’s exactly what has happened. ❂ © 2023 Dr. David Keegan ➲

❦ Always Covid+ Colleague: — “One of the medical groups. One of the groups. One of the groups...” Moderator: — “Is there something you want to share?” Always Covid+ Colleague: — “I was asked something. I don’t know. It has something to do with something.” This is what Covid is doing to the brain. Unfortunately this is not an isolated incident – but something I’m witnessing all day long throughout the company. ❂ © 2023 Lady Chuan ➲

✻ Accessed: 4 Dec 2023. ➲ Date published: 9 May 2023. ➲ Date last updated : 2 Oct 2023 . ❦ Executive summary Ventilation * is an important line of defence for infection control in the healthcare environment . Its design and operation are described in Health Technical Memorandum (HTM-03-01) . The current focus on ventilation has highlighted areas of high risk due to poorly performing and inadequate ventilation in hospitals and other healthcare settings. This may be due to change of room use, age, condition of air handling plant, lack of maintenance, challenges with effective use of natural ventilation or other. It is therefore important to bring these facilities up to the minimum specification of current standards , particularly recognising the challenges of COVID-19 and other infections . Local HEPA filter-based air cleaners (also know as air scrubbers) are one option for improving and supplementing ventilation. The installation of a high efficiency particulate air (HEPA) filter air cleaner can reduce the risk of airborne transmission . This guidance has been written as an interim specification to set the basic standard required for HEPA filter devices to be utilised in healthcare and patient-related settings . This edition is primarily aimed at portable and semi-fixed (wall-mounted) devices. Devices relying on ultraviolet light (UVC) are the subject of a separate guidance document: Application of ultraviolet (UVC) devices for air cleaning in occupied healthcare spaces . * Ventilation is the process by which ‘fresh’ air (normally outdoor air) is intentionally provided to a space and stale air is removed. This may be achieved by mechanical systems using ducts and fans, or natural ventilation most commonly provided through opening windows. The local redistribution of air may also be construed as ventilation. 1. Introduction Ventilation is an important feature in the control of airborne infection . However, the emergence of SARS-CoV-2 as a highly contagious virus has demanded new and innovative solutions to safeguard patients , staff and visitors . Health Technical Memorandum 03-01 Specialised Ventilation for Healthcare Premises (HTM-03-01) is a robust standard for ventilation of higher risk clinical spaces based on high air-change rates using outdoor air to continually flush indoor spaces. The COVID-19 pandemic has shown that greater attention must be paid to the improvement and maintenance of ventilation in healthcare settings . The focus on ventilation has also highlighted areas of high risk due to poorly performing and inadequate ventilation , particularly in older hospitals and other healthcare settings such as primary care and dental suites, which increase risks of nosocomial infections. In cases, where current ventilation does not meet HTM-03-01 standards, this may be due to age, condition of air handling plant, lack of maintenance or other design or operational issues. In the case of naturally ventilated spaces, there is a reliance on staff or patients opening windows. Weather conditions, external noise and air pollution and restricted window openings for safety affect the ability to open windows and means that ventilation in some settings can fall below recommended rates. Local HEPA filter air cleaners are one option for improving and supplementing ventilation . The correct installation and operation of a HEPA filter air cleaner can reduce the risk of airborne transmission . Healthcare trusts are under pressure to improve ventilation and in the meantime are considering options including filter-based air cleaning. This standard will assist trusts in selecting and implementing good quality, reliable equipment. There is substantial evidence from laboratory studies and real-world settings that filtration is an effective technology for reducing airborne pathogens within room air and HVAC systems. A number of research studies have been carried out which indicate that measured levels of micro-organisms in air are greatly reduced by air filters [R1-R5, R7] . There is also evidence which directly associates use of filter-based air cleaners with reductions in infection rates of environmentally-derived aspergillus [R8] . The potential of air scrubbers employing UVC or HEPA technology to mitigate SAR-CoV-2 risks is the subject of a rapid review (September 2022) [R.9] . Filter-based air cleaners also remove other particulate matter and so can also reduce exposure to other air pollutants. However, air cleaners should not be used as a reason to reduce ventilation and care must be taken to ensure sufficient fresh air changes are provided for the dilution of medical gases and noxious odours, and the maintenance of appropriate oxygen and carbon dioxide levels to satisfy the Building Regulations Part F. This document aims to serve as interim guidance and regulatory reference point for the design and correctly engineered deployment of HEPA filter devices in real-world settings with regard to effectivity and safety. It focuses on HEPA filter-based devices which can be positioned locally within a room; the document does not cover HEPA filters used within HVAC ducts. Local filter-based devices require fan-assisted circulation to introduce the room air into the device, pass it through the filters and then to reintroduce the processed air into the room. An important consideration regards the flow of the air which is induced, processed and distributed by the device external to the device itself. The design and placement of the device should promote efficient air distribution in the room space and avoid short-circuiting of air circulation relative to furniture, obstructions, and occupancy. 2. HEPA filter technology HEPA filters comprise a porous structure of fibres or membrane which remove particles carried in an air stream. The mechanism by which particles are removed depends on the size of the particle. Larger particles are removed by impaction onto the filter while smaller particles <1 μm are removed through interception and diffusion. Interception occurs where the particle makes physical contact with the media fibres because particle inertia is not strong enough to enable the particle movement to continue. Diffusion is where random motion (Brownian motion) of the particle enables it to contact the media. These effects are enhanced by the electrostatic charges present on filters. 2.1 Selection of filters Filter efficiency defines the fraction of particles removed and varies by size of particle. The most difficult size of particles to remove, known as the most penetrating particle size (MPPS), for the majority of filters is around 0.3 μm; particles larger or smaller than this size are captured more effectively. For healthcare applications it is recommended that devices should contain filters classified as High Efficiency Particulate Air Filters (HEPA) under BS EN 1822-1 or ISO 29463-1 . HEPA filters have a filter efficiency of at least 99.95% (H13 filter) or 99.995% (H14 filter) for the MPPS, however the performance in situ is sometimes lower depending on the filter and device design and the air flow rate ( section 5.1 ). Micro-organisms range in size from around 0.1 μm for the smallest viruses to several μm in diameter for larger bacteria and fungi . Some fungi and bacteria may be dispersed independent of other material, however, many pathogens will be released on or within another material and therefore the size of the particle that needs to be captured is larger than the pathogen itself. For example, respiratory and gastroenterology viruses will be released within liquid media that contains proteins, salts, surfactants, etc and evaporates to form particles that are larger than the virus itself. Similarly, many skin associated bacteria are released on skin squame which are larger than the bacteria. Some filter-based air cleaning devices contain lower grades of filter. These devices may be appropriate in non-clinical areas, but as the filters have a lower performance for particles relevant to the size of airborne pathogens they are not recommended in settings with vulnerable patients. It is common for HEPA filter-based devices to incorporate a coarse grade of filter (typically ISO ePM10 >50% under ISO 16890-1 ) to act as a dust filter. Some also include a carbon filter to manage odours and volatile organic compounds. Some devices contain several separate filters, while others incorporate the different stage filters into a single cartridge type unit. 2.2 Inclusion of other technologies Devices which include germicidal ultraviolet (UVC) light alongside HEPA filters are likely to be effective [R4] . Where these devices are considered, this standard takes precedence in terms of clean air performance if the UVC lamp is located after the HEPA filter (i.e. the HEPA filter is the primary device for microbial removal). However, all the safety requirements pertaining to the UVC within that standard should also be complied with. Devices which incorporate ionisation, photocatalytic oxidation, electrostatic precipitation or other similar technologies alongside filters are not currently recommended for healthcare use unless there is clear evidence for both effectiveness and safety. These devices can sometimes introduce, or create through secondary reactions, chemical by-products into a room which may themselves have an adverse health effect [R4, R11] . The independent research evidence that these products are any more effective at safely reducing microbial loads in air is still emerging. 3. Applications and sizing Stand-alone, floor-mounted devices can be positioned at any suitable location in a room . These devices are plugged into a standard electrical socket so do not require any installation, although location is important as detailed in sections 8.2 and 8.3. Fixed devices are semi-permanently mounted to a wall or ceiling. These devices will normally be permanently wired into the room electrical systems rather than plugged into a wall socket. Some manufacturers offer local systems that can be interfaced with the ventilation system and are able to offer pressure differential control in a room. In rooms without natural or mechanical ventilation , or where the ventilation falls short of statutory requirements or regulatory advice , auxiliary devices may be deployed to enhance the equivalent air changes. The installation of HEPA filter-based air cleaners can be considered to contribute additional ‘equivalent’ air changes (eACH). For example, a treatment room with 6 ACH could achieve the equivalent of 10 ACH by installing a local filtration unit which recirculated and cleaned the equivalent of 4 eACH. Hence, to meet the requirements that comply with HTM-03-01 , the number of devices required will be dictated by the existing background levels of ventilation. The high filter efficiency of HEPA filters means that the single pass efficiency of an air cleaning device for the MPPS should result in at least a 99% (2 log) reduction in the concentration of particles, including microorganisms, that pass through the device when in normal operation. However, the performance within a room depends on both the flow rate through the device and how it distributes the air in a room. The performance of filter-based devices is described by some manufacturers in terms of a Clean Air Delivery Rate (CADR) which is usually expressed in metres cubed per hour (m 3 h -1 ) (some devices quote the CADR in cubic feet per minute, cfm). Where a CADR is given it should be derived from measurements of how well the device removes a defined size of particles in a test room environment; CADR is usually measured using particles rather than microorganisms. CADR is a function of the airflow rate through the device, the quality of the filter and the way the device distributes air in the test room. Other manufacturers adopt different metrics such as the time to reduce particle concentrations in a room by a specific percentage. The CADR or other metrics can be used, with care, for design purposes as they express how the device will perform in a standardised test room. However, it is important to note that the actual performance will depend on the particular location and operation of the device, including the room size, layout, background ventilation, device design and maintenance ( section 8 ). It is not recommended to use an air cleaning device with a lower grade of filter even if the quoted CADR is high, as the device may be less effective against the smallest pathogen-carrying particles. The CADR used for design purposes should be the rate applicable to the device setting at which the device is most likely to be operated and where the noise level is during operation is at a level of ≤50 dB measured at 3 m (dB 3m ) ( section 5.3 ). ❂ Bibliography Laboratory chamber studies demonstrating effectiveness of HEPA filter devices against particles and microorganisms [R1] Miller-Leiden S, Lohascio C, Nazaroff WW, Macher JM (1996) Effectiveness of in-room air filtration and dilution ventilation for tuberculosis infection control. Journal of the Air & Waste Management Association 46: 869–882. doi:10.1080/10473289.1996.10467523 [R2] Offermann FJ. et al (1985) Control of respirable particles in indoor air with portable air cleaners. Atmospheric Environment 19: 1761–1771. doi:10.1016/0004-6981(85)90003-4 [R3] Ueki H, Ujie M, Komori Y, Kato T, Imai M, Kawaoka Y (2022) Effectiveness of HEPA filters at removing infectious SARS-CoV-2 from the air. mSphere 7(4):e0008622. doi:10.1128/msphere.00086-22. [R4] Beswick A, Brookes J, Rosa I et al. 2022. Room based assessment of mobile air cleaning devices using a bioaerosol challenge. Applied Biosafety Journal. Published online Dec 2022. doi:10.1089/apb.2022.0028 [R5] Lindsley WG et al (2021) Efficacy of portable air cleaners and masking for reducing indoor exposure to simulated exhaled SARS-CoV-2 Aerosols — United States, 2021. Morbidity and Mortality Weekly Report (MMWR) 70: 972—976. doi:10.15585/mmwr.mm7027e1 Testing approach for Clean Air Delivery Rate [R6] Foarde KK, Myers EA, Hanley JT, Ensor DS, Roessler PF (1999) Methodology to perform clean air delivery rate type determinations with microbiological aerosols. Aerosol Science and Technology 30: 235–245. doi:10.1080/713834074 Application of HEPA devices in healthcare setttings [R7] Conway Morris A, Sharrocks K, Bousfield R, et al, The Removal of Airborne Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and Other Microbial Bioaerosols by Air Filtration on Coronavirus Disease 2019 (COVID-19) Surge Units. Clinical Infectious Diseases, Volume 75, Issue 1, 1 July 2022, Pages e97–e101, doi:10.1093/cid/ciab933 [R8] Abdul Salam ZH, Karlin RB, Ling ML, Yang KS. The impact of portable high-efficiency particulate air filters on the incidence of invasive aspergillosis in a large acute tertiary-care hospital. American Journal of Infection Control. 2010 May;38(4):e1-7. doi:10.1016/j.ajic.2009.09.014 . [R9] Bowles C, et al. A rapid review of supplementary air filtration systems in health service settings. September 2022. doi:10.1101/2022.10.25.22281493 medrxiv preprint. Wider reading on air cleaning applications [R10] Medical Advisory Secretariat. Air cleaning technologies: an evidence-based analysis. Ontario health technology assessment series vol. 5 (2005) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3382390/ [R11] SAGE-EMG: Potential application of air cleaning devices and personal decontamination to manage transmission of COVID-19, 4 November 2020 . https://www.gov.uk/government/publications/emg-potential-application-of-air-cleaning-devices-and-personal-decontamination-to-manage-transmission-of-covid-19-4-november-2020 ❂ 📖 (2 Oct 2023 ~ NHS England) NHS Estates Technical Bulletin (NETB 2023/01A): application of HEPA filter devices for air cleaning in healthcare spaces: guidance and standards ➤ ✻ Accessed: 4 Dec 2023. ➲ Date published: 9 May 2023. ➲ Date last updated : 2 Oct 2023 . © 2023 NHS England.

✻ Accessed: 4 Dec 2023. ➲ Date published: 9 May 2023 . ➲ Date last updated : 2 Oct 2023 . ❦ Applicability ‘This NETB applies to all healthcare spaces with ventilation requirements. Objective To provide additional technical guidance and standards on the use of UVC devices for air cleaning in healthcare spaces. Status The document represents advice for consideration by all NHS bodies . It is to be read alongside Health Technical Memorandum 03-01 Specialised Ventilation for Healthcare Premises (HTM 03-01) . Executive summary Ventilation * is a key line of defence for infection control in the healthcare environment . Its design and operation are described in Health Technical Memorandum (HTM-03-01) . The current focus on ventilation has highlighted areas of high risk due to poorly performing and inadequate ventilation in hospitals and other healthcare settings due to age, condition of air handling plant, lack of maintenance, challenges with effective use of natural ventilation or other creates areas of high risk. It is therefore important to bring these facilities up to the minimum specification of current standards, particularly recognising the challenges of COVID-19 and other respiratory infections . Ultraviolet (UVC) air cleaners (also known as air scrubbers) using ultraviolet light are one option for improving and upgrading ventilation. The installation of a UVC air cleaner can reduce the risk of airborne transmission . This document has been written as an interim specification to set the basic standard required for UVC devices to be utilised in healthcare and patient related settings. This edition is primarily aimed at portable and semi fixed (wall-mounted) devices. The series will extend to in-duct and upper room devices in future iterations. Devices relying on HEPA filters or similar filter-based technology can have similar benefits to UVC devices but are not considered in this document. The potential of air scrubbers employing UVC or HEPA technology is the subject of a rapid review (September 2022) . * Ventilation is the process by which ‘fresh’ air (normally outdoor air) is intentionally provided to a space and stale air is removed. This may be achieved by mechanical systems using ducts and fans, or natural ventilation most commonly provided through opening windows. The local redistribution of air may also be construed as ventilation. 1. Introduction Ventilation is a critical feature in the control of airborne infection . However, the emergence of SARS-CoV-2 as a highly contagious virus has demanded new and innovative solutions to safeguard patients , staff and visitors . Health Technical Memorandum 03-01 Specialised Ventilation for Healthcare Premises (HTM-03-01) is a robust standard for ventilation of higher risk clinical spaces based on high air change rates using outdoor air to continually flush indoor spaces. The emergence of COVID-19 has shown that greater attention must be paid to the removal or deactivation of airborne pathogens in areas where ventilation rates are lower. The focus on ventilation has also highlighted areas of high risk due to poorly performing and inadequate ventilation , particularly in older hospitals and other healthcare settings such as primary care and dental, which increase risks of infection spread viz nosocomial infections . In cases, where current ventilation does not meet HTM-03-01 standards, this may be due to age, condition of air handling plant, lack of maintenance or other design or operational issues. In the case of naturally ventilated spaces, there is a reliance on staff or patients opening windows. Weather conditions, external noise and air pollution and restricted window openings for safety affect the ability to open windows and means that ventilation in some settings can fall below recommended rates. UVC air cleaners using ultraviolet light are one option for improving and upgrading ventilation. The correct installation and operation of a UVC air cleaner can effectively reduce the risk of airborne transmission. NHS trusts are under pressure to improve ventilation and are considering options including UVC air cleaning. This standard will assist trusts in selecting and implementing good quality, reliable equipment. There is substantial evidence from laboratory studies and real-world settings that UVC is an effective technology for reducing airborne pathogens within room air and HVAC systems. A number of trial ‘case studies’ have been carried out which indicate that measured levels of micro-organisms in air are greatly reduced and infection rates have decreased. These trials have also shown that UVC within HVAC systems safely allows some levels of air recirculation and can achieve substantial energy reductions compared to the normal 100% fresh air approach set out in HTM-03-01. For example, a scheme with 50% fresh air and 50% recirculated air would reduce heat demand by 50%. However, care must be taken to ensure sufficient fresh air changes are provided for the dilution of medical gases and noxious odours, and the maintenance of appropriate oxygen and carbon dioxide levels. This document aims to serve as interim guidance and regulatory reference point for the design and correctly engineered deployment of germicidal UVC devices in real-world settings with regard to effectivity and safety. 2. UVC germicidal effects There are a wide range of UVC devices which aim to inactivate microorganisms in the air and/or on surfaces. This document focuses on contained UVC devices which can be positioned locally within a room or within an HVAC duct. These devices usually require fan-assisted circulation to introduce the room air into the device, expose it to ultraviolet light and then to reintroduce the processed air into the room. Therefore, aerodynamics internal to the device together with the lamp specification determines the air and microbial particle UVC exposure time and hence the radiation dose. These devices are known as active UVC air cleaning devices . Not considered in this document are passive UVC devices, aka upper room devices, which rely on the natural air currents within rooms. An important consideration regards the flow of the air which is induced, processed and distributed by the device external to the device itself. The design and placement of the device should promote efficient air circulation in the room space and avoid short-circuiting of air circulation relative to furniture, obstructions, and occupancy. The ultraviolet-C (UVC) spectrum lies in the interval [200…280] nm. UVC irradiation as a means of microbial inactivation has been used for over 100 years in multiple sectors including medical, scientific, water disinfection, manufacturing and agricultural. UVC germicidal activity inactivates microorganisms rendering them unable to replicate. Most commonly, germicidal activity is generated by mercury ionisation lamps with the major spectral line at 254 nm wavelength. This is sometimes also known as germicidal ultraviolet (GUV) or ultraviolet germicidal irradiation (UVGI) . This standard uses the term UVC . Recent studies suggest that devices based on far-UV (222 nm wavelength) may also be effective ; however, these are not covered here. The photo-toxicity risks associated with UVC is universally recognised. The design, specification and implementation of germicidal UVC solutions currently lacks rigorous governance and the requirement for regulatory change is recognised. The purpose of this standard therefore is to establish the key criteria for successful and reliable long-term application of UVC air cleaning while avoiding the potential safety hazards and operational pitfalls, particularly when equipment is used in spaces occupied by non-technical people. 3. Applications This standard covers the types of UVC air cleaners used as standalone or in-duct units where the principal active element is UVC at the nominal wavelength of 254 nm. In rooms without natural or mechanical ventilation, or where the ventilation falls short of local requirements or regulatory advice , auxiliary devices may be deployed to enhance the effective air changes. The installation of UVC air cleaners can be considered to contribute additional ‘equivalent’ air changes (eACH). For example, a treatment room with only 2 ACH could achieve the equivalent of 10 ACH by installing a UVC unit which recirculated and cleaned the equivalent of 8 ACH (eACH) for the micro-organisms of concern. Hence, to meet the requirements that comply with HTM-03-01, the number of devices required will be dictated by the existing background levels of ventilation. In-duct HVAC systems In buildings with existing HVAC systems which have recirculation of air, it can be effective to install UVC lamps directly into the ducts, placing them downstream of pre-existing particulate filters. This allows for the treatment of all rooms in the building covered by the HVAC system or within branch ducts serving various zones and the rooms within those zones. Due to the lamps being contained within the ducts, the risk of direct exposure to UVC is low. However, maintenance can be carried out; safely shut-down interlocks should be fitted and hazard notices compliant with BS EN ISO 7010 prominently displayed. 254 nm devices covered in this standard ❂ In-duct UVC: UVC lamps are installed directly into the HVAC system or are contained within a locally installed ventilation device which is connected into the HVAC system, similar to a fan-coil unit. Devices may use the fans and filters within the existing HVAC system or, in some cases, may have local fans and filters to provide the recirculation. Significant modelling and design are required to implement such systems. ❂ Floor standing UVC ‘mobile’ devices: UVC lamps are contained within a standalone floor mounted device that can be positioned at any suitable location in a room. These devices provide local air cleaning within a room and are plugged into a standard electrical socket so do not require any installation. The device contains lamps, dust filters and a fan to draw room air through the device. Devices are portable and so can be easily moved. ❂ Fixed UVC devices – wall or ceiling mounted: Similar to floor standing units but fixed to a wall or ceiling. These devices will normally be permanently wired into the room electrical system rather than plugged into a wall socket. UVC devices not covered in this standard ❂ Decontamination UVC devices: High intensity open-field UVC devices that are designed for periodic surface decontamination in unoccupied spaces. These devices are sometimes known as UVC robots. ❂ Upper-room UVC devices: UVC devices which utilise an open UV field within the room above the heads of occupants. These are passive devices which rely on the general circulation of room air and are sometimes assisted by ceiling fans. ❂ Devices based on other parts of the UV spectrum: The devices covered in this standard are based on 254 nm wavelength lamps. There are a number of other UV technologies including Far UV (222 nm) which has early data showing it is likely to be effective. ❂ Devices that incorporate other technologies alongside UVC: There are a number of devices which use UVC alongside other technologies such as titanium dioxide catalysts or ionisers. These devices often emit by-products into the room, either intentionally or deliberately. The health impacts of any emissions must be carefully considered.’ ❂ * Additional info. Source Sans Pro Normal 21/18. 1st row, 4th Colour. ❂ 📖 (2 Oct 2023 ~ NHS England NHS Estates Technical Bulletin (NETB 2023/01B): application of ultraviolet (UVC) devices for air cleaning in occupied healthcare spaces: guidance and standards ➤ ✻ Accessed: 4 Dec 2023. ➲ Date published: 9 May 2023. ➲ Date last updated: 2 Oct 2023 . © 2023 NHS England.

✻ Accessed: 4 Dec 2023. ➲ Date published: 24 Jan 2023. ➲ Date last updated: 2 Feb 2023. ❦ The UKHSA’s definition of ‘ Airborne ’, and how it applies to SARS-CoV-2 / COVID-19 : ➲ ‘ Airborne (droplet or aerosol) transmission : This occurs when an infected person coughs, sneezes, or talks (droplets) containing the infectious agent are expelled into the air and inhaled by someone nearby OR when an infectious agent is suspended in the air and inhaled by someone (aerosol) because the infectious particles are much smaller and can remain suspended in the air for long periods of time . For example flu, RSV, COVID-19 , TB, measles, C. diphtheria, Strep pneumoniae.’ ❂ ➲ [C19.Life Note ] : The accepted scientific definition of ‘airborne aerosol transmission’ most certainly also includes the act of breathing . While the UKHSA admits to close-range SARS-CoV-2 transmission via droplet (and aerosol), it neglects to emphasise far-range transmission via infectious aerosols. ❂ 📖 (24 Jan 2023 / Updated 2 Feb 2023 / Accessed 4 Dec 2023 ~ UK Health Security Agency) UKHSA Advisory Board: preparedness for infectious disease threats ~ Airborne (droplet or aerosol) transmission ➤ © 2023 UKHSA .