
Aerosol and surface stability of SARS-CoV-2 compared to SARS-CoV-1 [pdf] - cycop
https://www.medrxiv.org/content/10.1101/2020.03.09.20033217v1.full.pdf
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mikekchar
I think the important result of this study is that HCov-19 has essentially the
same half life on every surface they tested as SARS-CoV-1 except cardboard.
"In general, there was no statistically discernable difference in half-life
between the two viruses on any given surface except for cardboard: all other
95% credible intervals for the difference in half-lives overlapped 0".

Importantly, "Our results indicate that the greater transmissibility observed
for HCoV-19 is unlikely to be due to greater environmental viability of this
virus compared to SARS-CoV-1."

Edit: Remove line number from copy and pasted quote. Also fixed SARS virus
name.

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Jedd
Can someone please explain if there's some semi-obvious subtext to the caveat
-- that greater comparative transmissibility is NOT due to comparative
longevity on surfaces.

Is there something else specifically, or is this just a general observation
that greater transmissibility must be due to 'some other factor(s)'?

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mikekchar
The longevity is exactly the same, therefore it is likely that the greater
transmissibility is due to a different factor. I think that's the only
reasoning that's going on.

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AstralStorm
Latency and silent cases is probably enough.

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jlmorton
About the same range as influenza, which is thought to be about 48 hours, but
significantly longer than most common cold viruses, which remain active for
only a few hours at most.

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dvasdekis
Validates the Chinese approach of essentially banning doorhandles - jam doors
open, and for those that can't be jammed, wrap them in cloth covered in
disinfectant.

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blackrock
I wish designers can now go with a kick button, that will allow you to open
the door.

Put the kick button a few inches off the floor, so anyone can easily kick it,
and it activates a mechanical arm that swings open the door for you. Mount it
on the wall next to the door, and of course, you will need two, one on each
side of the door.

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stygiansonic
Aside: this paper demonstrates an interesting use of Bayesian regression to
get the full posterior distribution over plausible decay rates rather than
just a single point estimate. See the last few pages.

Is this pretty normal in these sorts of papers?

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splittingTimes
That means any items you buy in a supermarket (greens wrapped in plastic,
toilet paper, packaged meet, tin cans) should be set aside at home for 3 days?
And you need to disinfect yourself after each round to the store...

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officialjunk
correct. also quarantine deliveries.

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splittingTimes
Could i use commercial UV-lights (like for tanning or medicinal appliance) and
illuminate the items to kill off the virus?

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raverbashing
Good question. I _suspect_ viruses are less UV-sensitive than bacteria

However the main issue is that protecting yourself from the UV blast might be
more complicated than just disinfecting the product using traditional means

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blackrock
It looks like we can now get COVID-19 from Amazon Prime. Free 2-day delivery
for all!

A tired warehouse worker, forced to work overtime by Jeff Bezos, with no
health insurance or paid sick time, and with a robot that watches his every
move to make sure he isn’t slacking, gets sick with the virus, and sneezes on
your order. The package gets delivered to you in 2 days, and you open it up,
and hold it in your hands, thinking the product is clean and sterile. Then 3
days later, you get a strange cough, then the next day, you develop a high
fever. Boom! You just got infected with COVID-19.

It didn’t come from China, but from your friendly (and sick) Amazon warehouse
worker.

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lukastr0
Perhaps it's a good idea to place copper tape on all door handles and other
frequently touched objects. It's certainly very cheap to do so. Here's some
discussion on that idea with more evidence:
[https://www.lesswrong.com/posts/LwcKYR8bykM6vDHyo/coronaviru...](https://www.lesswrong.com/posts/LwcKYR8bykM6vDHyo/coronavirus-
justified-practical-advice-thread)

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AstralStorm
Silver could be even better. (including nanosilver coating as used in some
food processing hardware such as refrigerators)

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joecai
> Caution: Preprints are preliminary reports of work that have not been peer-
> reviewed. They should not be relied on to guide clinical practice or health-
> related behavior and should not be reported in news media as established
> information.

Now I really hope this report turns out to be flawed.

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hanche
So do I, but it still seems prudent to act like it is true: The extra hygiene
measures are a very minor inconvenience, especially compared to the major
inconvenience of catching the virus.

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milemi
If I have to be hospitalized, and nobody should enter my apartment for three
days to take care of my cats, and it turns out it’s unwarranted, that’s a big
inconvenience for me.

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xbmcuser
Get an auto feeder for food and water that can feed your cats when you are not
around for 5-6 days.

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sporkologist
I like to think of it as, the US is one big cruise ship but with coronavirus
instead of norovirus.

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jekdoce
Reading that the virus is stable in the air for 3h, you would think that the
R0 would be closer to measles, i.e. ~18 instead of ~2. Any ideas why this is
not the case?

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AstralStorm
Lack of symptoms in many more cases, for longer time. If measles had no
symptoms for a week, it'd spread way more easily.

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seizethecheese
The half life estimate is more interesting. 13hours on steel. 16 for plastic.

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foepys
Is it? Don't all viruses die after a more or less fixed timespan? Do they
decay like radioactive elements?

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sagebird
If viruses died at a fixed timespan, I think that would point to there being a
stateful element that keeps track of elapsed time, like a molecular sand
timer.

If viruses die because of spontaneous reactions, eg interaction with surfaces,
interactions with photons, or a spontaneous chemical reaction like oxidation,
then I would expect half-life decay similar to radioactive elements.

I don't know how viruses die. I wonder if they can be preserved near
indefinitely in a non reactive gas or vacuum in the dark.

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lerie1982
Why weren't other materials tested? Brick, concrete, woods?

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zakki
What is the temperature (room temperature) during the test?

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skolos
21-23 degrees Celcius, 63% humidity

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throwGuardian
Has anyone considered the probability of the virus spreading via overnight
e-commerce packages inadvertently containing infected steel/plastic?

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mvid
Don’t many overnight packages go through some really cold (warehouse/flight)
or really hot (desert trucking) scenarios? I imagine it’s mostly viable in
comfortable human conditions

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cheschire
It is my understanding that viruses tend to enjoy cold, and the temperatures
aren't deep enough to kill them.

Also why don't we say virii anymore?

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hanche
Because loan words tend to get adapted to the grammar of the host language
with time?

