Cyprus-Forum.com

[Londonrake]

https://www.telegraph.co.uk/health-fitn ... o-protect/

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[repulsewarrior]

...paywalled, (for me).

[Londonrake]

The science of airborne viruses: how particles move and what you can do to protect yourself
As a new study suggests that coronavirus particles could linger in the air for longer than previously thought, we unpick the science

How long can coronavirus particles survive in the air? It sounds like a simple question, perhaps one that should have already been answered, three months into the biggest medical crisis of a century, which is now responsible for more than 3.2 million infections and 233,000 deaths across the world, including more than 177,454 infections and 27,510 deaths in Britain.

But it is actually one of the issues on which virologists are most uncertain. Here, experts explain what we do know - and what still remains a mystery.

What happens when coronavirus particles leave your mouth?
When you cough or sneeze, you emit thousands of droplets, like rain. They are essentially tiny drops of saliva - scientists only call them droplets because they are invisible to the naked eye.

These droplets contain particles. The largest and heaviest of the particles will fall straight to the ground, whilst the smallest - known as aerosols - will continue to float about in the air for some time.

If you have Covid-19 (even if you are not showing symptoms) then your droplets will contain particles of the SARS-CoV-2 virus - a member of the coronavirus family, responsible for the Covid-19 disease.

Scientists generally agree that the most likely route of transmission for the coronavirus is if somebody coughs or sneezes in your close vicinity, and their droplets land on a wet part of your face - your eyes, nose, or mouth.

The droplets can fly about three feet before dropping to the ground, or six feet if the cough is particularly forceful, scientists say.

Another way is if you touch a common-handled object that somebody has recently coughed onto, like a doorknob or mobile phone, and then touch a wet part of your face.

But can they linger in the air?
Virologists have generally been working on the assumption that, unlike other droplets in your breath, SARS-CoV-2 particles cannot linger in the air for hours after somebody coughs. Indeed, an analysis of 75,000 cases in China conducted by the World Health Organisation found no evidence for this sort of airborne transmission.

But that assumption is now being challenged. A study published this week in the journal Nature Research looked at two hospitals in Wuhan, China.

By setting up ‘aerosol traps’ around the buildings, researchers found bits of the virus’s genetic material floating around indoor toilets, as well as a room in the hospital where medical staff removed their masks, gowns, and gloves.

Led by Ke Lan of Wuhan University, the researchers say their findings supports the idea that SARS-CoV-2 particles might be able to hang around in the air for hours, highlighting the importance of good indoor ventilation.

The study did not try to answer whether those virus particles were actually causing infection - they might have been dead or degraded particles.

Another investigation of a restaurant in Guangzhou, China, found traces of SARS-CoV-2 in the air conditioning system - suggesting that particles of the virus were being blown about the restaurant. The restaurant became the target of investigation after one diner was found to have infected nine others while eating there.

These are only small studies, of course, but scientists stress that there is still a huge amount we don’t know about how coronavirus is transmitted. Prof Lawrence Young, a professor of Molecular Oncology at the University of Warwick, says the Wuhan study shows that the virus can contaminate rooms in hospitals where medics remove their PPE, but adds: “Detecting the virus genetic material with a very sensitive test is not the same as detecting infectious virus. Dead or degraded virus would still be detected with this technique.”

He adds: “We still don’t fully understand how the new coronavirus spreads, but we’re learning more every day.”

Where are the hotspots?
Because it is seen as unlikely that SARS-CoV-2 can linger in the air for hours, there has been very little public information on how you can protect yourself from these small, airborne particles. Television and bus stop adverts produced by Public Health England (PHE) tend to focus on regular hand washing, for example, which provide little protection against airborne particles.

But if the novel virus can linger in the air, where is it most likely to gather?

Kevin Bampton, CEO of the British Occupational Hygiene Society, says that direct sunlight does a good job of killing virus particles. The ultraviolet rays break down its fatty outsides, he says, and “it’s not going to survive long” - so it’s generally better to be in a sunny outdoor environment than a stuffy, indoor one.

And if you are inside, much depends on the level of ventilation. “A mechanically ventilated area - somewhere that has lots of air blowing through it - is less problematic than an unventilated area.”

He says that poorly-ventilated train and bus carriages are likely to be particularly vulnerable to airborne particles, as are lifts.

“Obviously a lift doesn't have a particularly strong ventilation system, you tend to have lots of people in them, you tend to be in close proximity, so it’s this sort of area which might be more problematic.”

Handily, the Federation of European Heating, Ventilation, and Air Conditioning Associations has released specific guidance and how best to ventilate a building in the era of coronavirus: leave the mechanical ventilator switched on for longer than usual, they say, and avoid “recirculation sectors” which re-pump the same air back into the room.

Which facemask is best?
The most effective facemask for filtering out those tiny, airborne particles is an FFP3 mask. These are fitted with a filter at the front which filters out 99 percent of particles, “and certainly catch those tiny particles, so even if [SARS-CoV-2] was airborne, an FFP3 would catch it,” says Brampton.

This is why the British Medical Association recommends that all front-line health workers wear these FFP3 masks.

At the next rung down is the FFP2 mask, sometimes known by the American name N95, which filters out about 95 percent of particles. These masks are unlikely to protect you from the very smallest airborne particles, says Brampton. “They are used for dust extractions and things like that - they’re not medical-grade masks.”

Below that are surgical masks, which filter out about 20 percent of particles, and homemade cloth masks, which filter out somewhere below 20 percent. These masks are not designed to protect you from airborne particles - their purpose is to stop you from infecting others, by preventing your cough droplets from spraying onto those in your vicinity. This is why the U.S. Centers for Disease Control - the American equivalent of PHE - recently told all Americans to wear cloth masks in public places.

[repulsewarrior]

...nothing new here, and it does not answer the questions: how long can it be suspended, how long does it survive on surfaces, can it infect other surfaces transferred for example from one surface to another by a hand, or shoes?

...are masks a great infectious hazard, since isn't in them that these viruses are caught, and gloves; how long does the virus thrive in these conditions? And garbage cans, i ask, how hazardous are they in this regard, given how they are used, today?

...the subject has been breached, pandemics have become a subject needing an arsenal of weapons, one of which is intelligence. In the months (and years) to come this topic will continue to warrant attention.

...speaking futuristicly, what about copper handrails, buttons and knobs?

[Londonrake]

I wasted 15 minutes of my valuable lockdown time there the it seems. Good luck, anyway.

[repulsewarrior]

...no. old news, to me.

You have a readership, since you write everyday; don't look at me as your source of solace : somehow i feel you are disappointed because i threw my thoughts into this topic (as i like to do) .

i write, everyday, too. (more than a decade; have you read my manifesto?) . do you follow my posts on, "Cypriotism", it seems a lonely crusade, except for the number of views that change.

...never mind the article, great topic, you'll see.