Coronavirus

[Darkfox021]

If ACE2 receptor is key. Then Germans should have more infected than Spain. It is nice to have similar demographic and health care to observe now. Both Germans and Spaniards are pretty fit compared to the US if you look at heart diseases and diabetes. So it might be one reason why USA has more cases of death.

US death ratio is poor for two reasons. Most importantly, no widespread testing has been done. Significant, but less important, the main deaths are in the most risky population.

 

[Causalien]

maybe, but the recent four in Washington state were from a nursing home with very sick/older residents.

I suspect that if the virus hit a similar European nursing home, the results would be the same.

And that's one of the things that I don't want to see happen, but curious about.

One of the first UK cases had an infected medic that visited a nursing home. That was a close one, but I wonder if there's something to it.

Also, I believe one of the potential country that will blow up is probably Egypt. There are report of tourists who went to egypt and contracted the coronavirus yet Egypt reported only 2 cases. What are the chances of a random tourist contracts coronavirus in a country with 2 confirmed cases.

 

[sixela]

Thats [sic] not true. The virus gets dispersed in droplets when the infected person coughs/sneezes. The droplet can land on a surface - and someone else can touch the surface a day later - and then touch their face and they can get the infection.

tl;dr: no.

The surface has to remain moist for more than a day for your hypothesis to actually come true. Those viruses DO NOT survive in dry residue from droplets. Those must be FRIGGIN' LARGE droplets to remain liquid for a day on a surface they landed on.

 

[JRP3]

Important information about the outbreak, from Reddit:

Seems reasonable.

 

[KSilver2000]

The surface formites are more of a worry at home when one member of the family is infected. Coughing is a bigger issue outside. When I go out nowadays I don't touch surfaces. What will get me are the people coughing. I know it's getting worse cause now when I walk down the street in downtown, there's constantly people I pass by that coughs. As in, at any moment, if I stop and listen, someone is coughing.

And the worst of the offenders cough... slightly angled up, no covering and big breath to maximize the expulsion of sputum so they feel better.

Coughing expulses droplets at 24m/sec and affect a range of 6m and stays in the air for 10 min. And these people, due to lack of disease prevention education, will walk down the whole street like that constantly coughing.

Haha.
Not trying to be a hater, but I’m also very concerned of kids who aren’t regularly reminded to cover when sneezing or coughing. Or when they do, they sometimes cough into their hands and go about their activity.

In a perfect world, those sick people would be courteous to wear a mask in public to help prevent community transmission.

 

[jerry33]

Thats not true. The virus gets dispersed in droplets when the infected person coughs/sneezes. The droplet can land on a surface - and someone else can touch the surface a day later - and then touch their face and they can get the infection.

This doesn't sound correct. The virus must be kept moist. If it lands on a dry surface it will die quickly.

 

[KSilver2000]

This doesn't sound correct. The virus must be kept moist. If it lands on a dry surface it will die quickly.

Very False.
I don’t know about Cov as I’m not sure whether it’s been researched yet, but the typical flu can stay active for up to 24-48 hours depending on the surface type it lands on.

 

[EVNow]

tl;dr: no.

The surface has to remain moist for more than a day for your hypothesis to actually come true. Those viruses DO NOT survive in dry residue from droplets. Those must be FRIGGIN' LARGE droplets to remain liquid for a day on a surface they landed on.

24 hours is the upper limit of various studies.

Basically not true that someone has to cough directly in to your mouth like OP said. BTW, the droplets could go about 6 ft from the person and hang in the air for 5 to 10 minutes. So, if someone coughs in the street and you pass through the area after 5 minutes you could catch it.

Obviously much smaller chance than - if you shook the person's hand.

Killing Flu Germs: What Works?

There have been studies of how long significant amounts of flu germs can survive on surfaces. Estimates range from a few minutes up to 24 hours, depending on the type of surface. (It lives longest on hard surfaces.)
​

How Long Does the Flu Virus Live on Surfaces?

The UK National Health Service says flu viruses can live on a hard surface for up to 24 hours and a soft surface for around 20 minutes. In 2008, Yves Thomas and colleagues at the University Hospital of Geneva found flu viruses thrive in wet environments. Viruses applied to Swiss franc notes survived up to 72 hours, but mixed with human mucus, one Type A strain remained active for 17 days.​

 

[sixela]

No, they don't have to cough right in your face.

But surfaces (unless wet) are much less of a problem (even though indeed on some porous surfaces a coronavirus can survive for longer than the roughly 2 hours it takes to die on surfaces like stainless steel, in part because those surfaces can enable it to survive in a pocket of fluid). It's not a boolean game: the longer the virus has to survive on an inclement surface, the more it dies and the smaller the remaining payload.

For cardboard or plastic I wouldn't say 24 hours is unreasonable, especially not if you want to err on the side of caution.

And yes, someone sneezing in his hand and then shaking yours is indeed a problem.

 

[KSilver2000]

tl;dr: no.

The surface has to remain moist for more than a day for your hypothesis to actually come true. Those viruses DO NOT survive in dry residue from droplets. Those must be FRIGGIN' LARGE droplets to remain liquid for a day on a surface they landed on.

There’s a particular few people who don’t like it when I post here, but I’m really just trying to stop the misinformation. Sorry, but this type of false absolute statements need to be contained.

If all viruses could really go away on its own, there would be no need to wipe down and disinfect surfaces of common areas at the end of such gatherings at school, daycare, gyms, etc because everything would be spotless clean again by next morning.

Fun fact: Did you know that some viruses, more so ones that are specific to animals, can even be active for weeks on a clean hard surface.

 

[AlexS]

There’s a particular few people who don’t like it when I post here, but I’m really just trying to stop the misinformation. Sorry, but this type of false absolute statements need to be contained.

Fun fact: Did you know that some viruses, more so ones that are specific to animals, can even be active for weeks on a clean hard surface.

You have been watchin too many fear mongering youtube videos.

 

[Causalien]

Haha.
Not trying to be a hater, but I’m also very concerned of kids who aren’t regularly reminded to cover when sneezing or coughing. Or when they do, they sometimes cough into their hands and go about their activity.

In a perfect world, those sick people would be courteous to wear a mask in public to help prevent community transmission.

By the way:

Face Mask Use and Control of Respiratory Virus Transmission in Households

and

https://annals.org/aim/fullarticle/...nsmission-households-cluster-randomized-trial

these are the links I saved. There were other studies on mask usage as well.

Problem with all these medical research is that as a non professional, the signal to noise is too high. You can find studies that proves the two polar opposite results.

 

[SarahsDad]

"Sequential schlieren images during the cough were recorded at 3000 frames per second. A maximum airspeed of 8 m per second (18 mph) was observed, averaged during the half-second cough. Several phases of cough airflow are revealed in the figure. The cough plume may project infectious aerosols into the surrounding air."

 

[EVNow]

You have been watchin too many fear mongering youtube videos.

See the links I provided. If you have better links - pls post them.

BTW, this is not idle speculation. Its for practical purposes. Basically would you
- clean the cart handle before starting to shop
- what about much used surfaces like door handles and elevator buttons in busy public places
- tables/chairs in restaurants

In general we have no idea how many minutes/hours before someone with infection touched those surfaces. You have to just follow a protocol, if you want to reduce the risk.

 

[sixela]

Fun fact: Did you know that some viruses, more so ones that are specific to animals, can even be active for weeks on a clean hard surface.

Yes. All too well, having had a norovirus infection spread to me from the previous occupant of an AirBnB in Amsterdam. Well, that wasn't a week, but it was more than a day.

 

[KSilver2000]

Another problem with research studies in general is bias. If you’ve found a topic of study interest, you usually have a bias to what you believe an outcome might be. And that can cause your data collection methodology or analysis to be skewed sometimes.

 

[KarenRei]

You have been watchin too many fear mongering youtube videos.

Alex is correct. There is a difference between the fact that a virus "can" survive for days or weeks, vs. how infectious a contaminated surface is. This starts declining immediately, and is significantly lower within a few hours. The fact that you "can" catch a disease from a contaminated surface days or even a couple weeks later does not mean that it's at all likely that you will.

Infection is all about probabilities.

This said: I'm not sure how much impact initial droplet size has on final droplet size. Droplets start evaporating immediately, regardless of their size, but as they evaporate, dissolved proteins, salts, and even the virus particles themselves reduce the vapour pressure over the droplet, to the point that it eventually matches the ambient humidity and evapouration ceases. The final size is thus related to what's in the droplet, and how much.

 

[sixela]

In general we have no idea how many minutes/hours before someone with infection touched those surfaces. You have to just follow a protocol, if you want to reduce the risk.

Of course that's one of the reasons it pays to wash your hands. Even if you pick up viruses on your hands, they're going to infect you when you bring that hand with disease vectors to your mouth...

I'm not saying that it's impossible to catch the virus by contact with hard sudrfaces (let alone porous ones). I do still think that in the grander scheme of things if you do get infected that's not the most likely transmission, but that's because airborne particles are so efficient in carrying the virus right from the previous host into your respiratory system.

 

[Causalien]

You have been watchin too many fear mongering youtube videos.

Eh?

I am pretty sure Ksilver is right here.

There was some virology researcher early on in January who got a batch of the virus from China and tested their survivability on surfaces. On smooth surfaces it survives for 9 days. Of course that's under ideal conditions. I can't find the research now, but porus was I believe 5 days. Then there's many others. I don't know if he has finalized and published his research yet.

There may be text books doctors study that says it is impossible. But experiments says otherwise.

 

[KSilver2000]

Alex is correct. There is a difference between the fact that a virus "can" survive for days or weeks, vs. how infectious a contaminated surface is. This starts declining immediately, and is significantly lower within a few hours. The fact that you "can" catch a disease from a contaminated surface days or even a couple weeks later does not mean that it's at all likely that you will.

Infection is all about probabilities.

This said: I'm not sure how much impact initial droplet size has on final droplet size. Droplets start evaporating immediately, regardless of their size, but as they evaporate, dissolved proteins, salts, and even the virus particles themselves reduce the vapour pressure over the droplet, to the point that it eventually matches the ambient humidity and evapouration ceases. The final size is thus related to what's in the droplet and how much.

ummm...

Funny thing Causalien mention that research. I was just looking at PubMed to see whether there has been any studies, and I found the article I think he was exactly referring to.
Hopefully, you guys can see this link since I have access to the portal:
https://www.journalofhospitalinfection.com/article/S0195-6701(20)30046-3/fulltext?mobileUi=0#sec5
Edit: Take a read. I believe it’s an interesting read even for most non-medical/science backgrounds. They go on to describe various solutions to inactivate in vitro.