The new COVID variant and how we should behave to be safe. tl;dr: it hasn't acquired resistance to anything; soap, distancing, masks and fresh air all still work; but we should act like people indoors are giving off more than they were.
First the science: the new variant is surrounded by the same lipid coating so still killed by washing hands with warm water + soap. Infection still carried in the same tiny droplets given off when breathing / talking; fresh air / masks / distance still reduce this transmission.
Difference is in the protein it makes and how it interacts with our bodies. Somehow easier to infect. So, either infected people breathe out more virus, or you need to breathe in less virus to get infected. But the actions we need to take are the same either way.
Before, for people indoors, I'd have suggested doing three out of: open windows; masks; short meeting (<20 minutes); >2m. Each cuts down the levels of virus in the air around five-fold. Now I'd suggest all four to be safe. Previous thread:
Before I'd have said outdoors completely safe ("1m plus"); now I'd make sure to stay 2m away or wearing a mask if sitting outside talking to someone. But going for a walk together still safe.
Also, no more likely to survive on surfaces (same lipids and RNA) - so still low risk. (Since more known about airborne infection, infection from surfaces considered much less of a risk than previously thought; very few documented cases of infection through surfaces)
Note: previous "COVID-safe" precautions in restaurants (sanitiser, distance, visors, perspex screens) were never safe for airborne viruses, without good enough ventilation; they were based on what was known at the time, but guidance and messaging needs to change.
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I've been asked - especially after public talks / twitter threads on aerosol disease spread - how I personally behave. A few things to bear in mind. 🧵
First - my background can tell you *relative* risks. That doubling ventilation or HEPA can halve your risk, and wearing FFP2 reduce it at least ten-fold, compared to without. But these don't tell you *absolute* risks... 2/
Are risks of catching COVID from going to that party like the flip of a coin, roll of a dice, or a single raffle ticket? The answer depends directly on the COVID levels where you are and when you ask. How many people you know are getting COVID is a clue. Not my expertise tho 3/
There have been a number of articles claiming recent findings from UEA show air filtration does not reduce the spread of Covid. But the pre-print shows the opposite
They did a systematic review of a number of different technologies at stopping a range of diseases. They found some were more effective than others. HEPA filtration, for example, consistently showed a 30% reduction in people with symptoms! So how does that give "ineffective"? 2/
The answer is that they combined ("pooled") the data for HEPA with other ineffective technologies, lumping them all together as "air cleaning". "Air conditioning" is worse than useless (see fig above and ) - but included cos it *might* have a filter 3/
Seasonal winter viruses driven by drier indoor air in winter. Why is it drier in winter, why does that make viruses spread more easily, and what can we do with that info? 🧵on article 👇 1/ annualreviews.org/doi/pdf/10.114…
"Isn't it driven by us spending more time indoors together when the weather's worse?" Probably not - in industrialised world, we spend most of our time together indoors anyway. So it's indoors that counts. 2/
Why is indoor air drier in winter? Cos it's come from outdoors, and it's colder outdoors, and colder air holds less water. (See graph below: Saturated = 100% "relative humidity" [RH]; actual amount of water in air is "absolute humidity" dx.doi.org/10.3389/fspor.…). 3/
Thread: How do we make the air in classrooms safer?
All you need to know about HEPA filters,CO2 monitors and ventilation. Contents: basic ideas; how to with links to resources; caveats; links to studies / evidence (that I'll add to cos takes more time) 1/
Airborne respiratory diseases (TB, Covid etc) are all transmitted the same way: pathogen is in tiny particles that we breathe out / give off when speaking. They're small enough to stay in the air like smoke; you get more if you’re closer but eventually the whole room is smoky 2/
People breathe them in, and get infected. More particles are given out through talking, shouting or singing. Because the virus is in these same particles, it doesn’t matter what variant of covid it is. nature.com/articles/s4159… 3/
Really interesting findings. tl;dr: rigourous study confirming that infectious COVID virus is found in the aerosol particles down to the tinest ones (<1 micron) that are given off in breathing and speaking, and can stay in the air for hours. Even more tl;dr: definitely airborne.
Previous studies have found viral RNA in aerosol particles that float in the air - but skeptics have suggested this is "dead" RNA. Other studies have tried and failed to grow actual COVID from these air-extracted samples - but that's just cos their experiments didn't work... 2/
...for whatever reason. This paper did it properly, and found you can extract the aerosols from air near patients, and the COVID in them can replicate. 3/
Keeping R<1 will become easier and easier with vaccination. Under these conditions, covid levels die away, and flare-ups can be stamped out.
Some "steady state" level of COVID" that we "live with" isn't a thing, cos that's not how exponential growth works. Definitely not where (1) we don't have to do anything restrictions-wise, and (2) we still have some control over that level.