Coronavirus and Masks Redux
When I wrote my original post I avoided discussing the research around coronavirus. Mostly this was because it was irrelevant to the piece but partly it was because I'm not a virologist or epidemiologist and didn't feel comfortable digging through the constantly-evolving research. But looking back it is now clear that while there was an understandably messy period where scientists were getting to grips with this novel disease, a scientific consensus was quickly reached. That consensus was that the initial advice on managing the pandemic was based on a flawed understanding of the virus.
Organisations and governments were quick to accept the initial, (understandably) flawed advice, but have been woefully lax at changing their messaging in line with changing science. I have to point out that in this regard the UK is not an outlier. The World Health Organisation was incredibly slow to accept the changing advice and that has, I suspect, led governments to feel justified in not changing their advice either.
Most Other Versions of Coronavirus Spread by Droplets
The original advice was based on how other versions of SARS-CoV virus were thought to spread. The consensus at the time was that they, and many other viruses such as flu, spread by droplets (this consensus is now being strongly challenged). Droplets are relatively large particles of mucus or saliva that come out of people's mouths and noses. While there are always droplets coming out, their numbers increase when we do things like talk, sing and cough. If those droplets contain particles of a virus like coronavirus then they can infect others who come into contact with them. That contact can be direct (breathing them in, or getting them on your skin which you then touch and get into your nose or mouth) or indirect (the droplets fall onto a surface which you then touch and transfer the virus particles to your nose or mouth). Because these droplets are relatively large they are also relatively heavy and fall out of the air quite quickly.
Knowing this, the original advice - social distancing, handwashing and avoiding touching things other people have recently touched - makes sense. Heavy droplets don't travel far so maintaining a distance of at least 2m from people means you're unlikely to breathe coronavirus in and so are at little risk of infection. Thus, outside of places like hospitals, wearing masks was seen as unnecessary. Handwashing and avoiding touching things means you're unlikely to get droplets on your hands and even if you do, you'll wash them off before you have a chance to get them into your nose or mouth. This led to advice to leave packages for 72 hours and to wash groceries. And people followed that advice.
But SARS-CoV-2 Spreads by Aerosols
SARS-CoV-1 (which was responsible for SARS outbreaks in the early 2000s) spread by air. It seems that SARS-CoV-2 has taken this adaptation and run with it, leading it to become more infectious and resulting in the pandemic we all know and love.
What do I mean by "spread by air"? Basically, that rather than being spread by those heavy droplets, the new coronavirus is spread by very light droplets that scientists call aerosols. These are generated in the same way as the droplets and are essentially the same thing, they're just a lot smaller. And because they're a lot smaller they stay in the air a lot longer. No-one is exactly sure how long they remain in the air or how long they remain infectious, though some estimates suggest in the order of hours.
What Does This Mean For The Advice We Are Given?
In short, this means that the advice we have been given is dangerously incorrect.
There is no evidence to suggest that touching contaminated surfaces is a major route of infections. Experts as long ago as last July were calling the the risk "exaggerated". And the focus on cleaning surfaces has distracted us from the real risks. The major route of infections is contaminated air: poorly ventilated
rooms with little or no airflow where coronavirus-containing aerosols
can linger for ages while people walk through them; breathing them in;
getting infected. Aerosol transmission was first proposed in April 2020. Dozens of papers were written providing more and more evidence that coronavirus is an airborne virus. Later in 2020 Dr Julian Tang, an honorary associate professor of respiratory sciences at the University of Leicester, told The Guardian,
“A lot of money has been spent, and time has been spent, deep-cleaning surfaces, when the main risk is probably people talking to each other,” he said. “If we had put that investment into masks earlier on, if we had put all the effort on hand washing and deep-cleaning into universal mask-wearing early on, we’d almost certainly not have such a massive epidemic in Europe and North America.”
Even now, over a year later, we still see people prioritising surface transmission over ventilation and masks. I've lost count of the places I've been where I've seen maskless staff disinfecting rarely-touched surfaces in the name of coronavirus prevention.
Why Masks Are So Important
When I wrote my original piece on masks I said the evidence for their effectiveness seemed equivocal. That is no longer the case. Masks have been shown to be effective at reducing transmission of coronavirus. There's still a lot of argument about exactly how effective they are, and it's clear that masks alone aren't sufficient to stop transmission, but masks are have few negative side effects (mostly around making it harder to understand people, particularly if you have hearing problems), are low cost and the way they work makes sense - preventing coronavirus particles from getting into the air means their primary source of transmission is cut off or at least severely limited.
The focus of my ire last year was the lack of specific advice on masks from the government. And that lack of advice is even more egregious now we know that coronavirus is spread by aerosols. When we thought it was spread by droplets, providing any sort of barrier between the nose and mouth and the rest of the world was adequate. Droplets are sprayed forward and then fall to the ground. A poorly fitting mask or a face shield is still sufficient to block most of those droplets. But when you're dealing with aerosols these barriers are nowhere near enough. Face shields, in particular, do nothing to block aerosols - they're basically portable sneeze-guards - and their open sides and bottoms allow aerosols to float free.
The messaging has been so consistently bad that most people still seem to think that masks are worn to protect them from other people. This is not the case. While masks do provide some protection to the wearer the main reason to wear them is to protect others by blocking the wearer's potentially-infected droplets and aerosols and preventing them from getting into the air. This is important because in around a quarter of coronavirus cases the person has no symptoms - you could be infectious and not know it.
Given this confusion it's no surprise that people decide not to wear masks. If they aren't worried about catching coronavirus why bother? It's not like they're hurting anyone. But they are hurting people. And most people, I like to believe, would have a different attitude to masks if this was more commonly known.
If the messaging had been clear from the start that wearing a mask is a selfless act of you protecting others then maybe we would have had higher compliance. Instead we have a Prime Minister refusing to wear a mask indoors at COP26 in contravention of Scottish guidance, and refusing to wear a mask in a hospital in contravention of English guidance. Presumably, having caught and survived coronavirus, Johnson feels that he has nothing to fear from it and so sees mask wearing as unnecessary. The idea of being someone who leads by example seems to have passed this Churchill-wannabe by.
Ventilation Is Also Important
Masks are just one tool in our arsenal against coronavirus. Vaccination is another, and we have had excellent uptake, though there has been high levels of hesitancy in ethnic minority communities for understandable reasons. Social distancing is still important, particularly when around people without masks. But the real key to ending this pandemic and preventing future ones is ventilation, and here too the government has been woefully slow off the mark. It was only this month that the government really started discussing ventilation. As part of their campaign materials they referenced a Department of Health and Social Care study which found that 64% of people were unaware of the importance of ventilation in stopping the spread of the virus. That is appalling.
Most people do not read scientific papers. Most people do not read long articles on websites and in newspapers. Most people read headlines and move on. This is why clear, concise advice is so important. And the government has consistently failed to provide it. Where are the posters and videos explaining that coronavirus is airborne? Where are the posters and videos showing people how to wear a mask? Where's the government-backed tick on masks that meet requirements for blocking coronavirus? Where are those requirements?!
We have been left floundering for so long. Scientists have worked tirelessly throughout the pandemic trying to work out what can be done to stop its transmission and came up with some really simple solutions - put a couple of layers of tightly-woven fabric over your face and open the windows and doors. Yet somehow that advice has not made it to the vast majority of the public and instead we are left with people disinfecting doors and counters all the while potentially breathing out coronavirus into the air for anyone to breathe in.
Where Now?
We are coming up to two years of this pandemic - the first official UK cases were detected in late January 2020 though there's evidence to suggest it had been around for a few weeks prior to that. Modelling by Cambridge university that estimates all cases, not just those that have been identified by a government-supplied test, suggests that there have been around 27 million cases of coronavirus in England - that's about half the population. At the beginning of the pandemic the aim seemed to be to eradicate coronavirus but with places like the UK and USA unwilling to control outbreaks and places like Africa (who have managed the virus far better than much of the west) unable to access vaccinations in anywhere near the volumes required, it seems that we are going to have to learn to live with it. This doesn't mean ignoring it and pretending everything is back to normal (which seems to be the British government's approach) but recognising that it is now something we must factor in to our daily lives. Hopefully it will become less virulent and more like flu (though that could take years, may not even happen, and it's worth remembering that flu kills around half a million people each year). But there's no guarantees.
Where this all leaves me is feeling bereft and angry. Not just at the unnecessary loss of so many lives and the hurt of those left behind. Not just for the people who are left living with long covid, whose lives have been changed forever. Not just for those working on the front lines in hospitals and care homes and shops who've not had a chance to rest and process what they've been through before being told to "get back to normal". And not just for every single person who have seen our lives derailed for the last two years.
Beyond all that we have seen how our government and the so-called "global community" respond to a crisis and that response has been nothing short of shameful. How on earth are we to tackle something as complex as climate change when we are so resoundly defeated by a simple virus? How are we to stand as moral authorities when our own government treated anyone with long-term health conditions as the walking dead and our own Prime Minister preferred to "let the bodies pile high" than call for another lockdown? How are we to ever trust our elected officials when they can't even follow the advice they gave? The pandemic has revealed a lot about how our society does (and doesn't) work. While our government may resist learning lessons, I hope that we aren't so reluctant.
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