Coronavirus 2019-2020 thread (no unsubstantiated rumours!)

AndrewS

Brigadier
Registered Member
Andy did you misstype? Today at 9:29 AM I said I started from Jan 29, not from your "Jan 18"

EDIT now noticed a certain type of
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did it pretty well

Jan 29 is labelled as the 11th day.

But Jan 23/24 was when the quarantine started and public awareness became widespread.
These measures should have sharply reduced the infectivity rate.

So the algorithm should really start at Jan 24.
 

mahakala

New Member
Registered Member
Persistence of coronaviruses on inanimate surfaces and its inactivation with biocidal agents
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A review paper suggests that 2019-nCOV may persist on metal/glass/plastics for up to 9 days.
Note that this is a literature review (a collaboration of other papers); The reviewed papers looked at several other coronaviruses (SARS, MERS, and other human coronavirus) to come to this conclusion. 2019-nCOV itself has not been tested on.
62-71% ethanol, 0.5% hydrogen peroxide or 0.1% sodium hypochlorite seems to be the best disinfectant to use - time to buy stocks on companies that make these!
 

solarz

Brigadier
Persistence of coronaviruses on inanimate surfaces and its inactivation with biocidal agents
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A review paper suggests that 2019-nCOV may persist on metal/glass/plastics for up to 9 days.
Note that this is a literature review (a collaboration of other papers); The reviewed papers looked at several other coronaviruses (SARS, MERS, and other human coronavirus) to come to this conclusion. 2019-nCOV itself has not been tested on.
62-71% ethanol, 0.5% hydrogen peroxide or 0.1% sodium hypochlorite seems to be the best disinfectant to use - time to buy stocks on companies that make these!

The question it doesn't seem to answer is how much of the virus persists, and what is the probability of being infected from touching such a surface.
 

mahakala

New Member
Registered Member
The question it doesn't seem to answer is how much of the virus persists, and what is the probability of being infected from touching such a surface.

I would quote from the paper itself(courtesy of sci-hub)

Results
Persistence of coronavirus on inanimate surfaces
Most data were described with the endemic human coronavirus strain (HCoV-) 229E. On different
types of materials it can remain infectious for from 2 hours up to 9 days. A higher temperature such
as 30°C or 40°C reduced the duration of persistence of highly pathogenic MERS-CoV, TGEV and MHV

The authors unfortunately did not elaborate on how they defined the term "remained infectious", my guess would be a certain threshold of viral load (as this is a pre-print the version I had access to via sci-hub might not be complete). These are all based on lab conditions so to draw directly conclusion in real life practice where there are much more different variables and confounding factors is almost impossible.

Often with these literature reviews different papers would have slightly different methodology and standards which adds further complexity.

Nevertheless it highlights the fact that these viruses do persist on inanimate objects for a significant amount of time, with a risk of transmission if someone else touches the said surface and then proceed to touch their mucosal areas (eyes/nose/mouth).

Gives justification to regular hand washing, alcohol gel sanitizer and avoid touching the face
 

Hendrik_2000

Lieutenant General
in the meantime
He spoke out about the Wuhan virus. Now his family and friends fear he's been silenced
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I have no doubt that China need to improve the epidemic early warning system which is shockingly absent and unresponsive now
The doctor is brave to be on the frontline of this fight just like hundred and thousand of his colleague. His sacrifice will be remember and appreciated

But the western press hype to make him poster boy for freedom of speech is in appropriate. He does not have channel to express his suspicion of the this virus. Even assuming that he is free to publish his finding It will create panic and pandemonium and Yes the Government response in inadequate.

Put yourself in any official shoe say calling it early what happened if the virus is just run of the mill influenza does it justify shutting down a city?. It is always easy to be armchair doctor
 
Jan 29 is labelled as the 11th day.

But Jan 23/24 was when the quarantine started and public awareness became widespread.
These measures should have sharply reduced the infectivity rate.

So the algorithm should really start at Jan 24.
not sure why you appear to insist on Jan 24, anyway I tabulate

a/(exp(-k*(DAY - xc))*(d - 1) + 1)^(1/(d - 1))

(coefficient values are in Today at 1:30 PM graph)

from DAY #5 = Jan 24

day#5 440 confirmed cases, back-calculated: 1598
day#6 571 confirmed cases, back-calculated: 2008
day#7 830 confirmed cases, back-calculated: 2523
day#8 1287 confirmed cases, back-calculated: 3168
day#9 2744 confirmed cases, back-calculated: 3974
day#10 4515 confirmed cases, back-calculated: 4976
day#11 6061 confirmed cases, fitted: 6218
day#12 7771 confirmed cases, fitted: 7745
day#13 9692 confirmed cases, fitted: 9604
day#14 11943 confirmed cases, fitted: 11838
day#15 14562 confirmed cases, fitted: 14469
day#16 17383 confirmed cases, fitted: 17492
day#17 20624 confirmed cases, fitted: 20853
day#18 24539 confirmed cases, fitted: 24440
day#19 28262 confirmed cases, fitted: 28089
day#20 31453 confirmed cases, fitted: 31605
day#21 34876 confirmed cases, fitted: 34810
day#22 37552 confirmed cases, fitted: 37574
23th day = Feb10: 39842 extrapolated from the fit
24th day = Feb11: 41625 extrapolated from the fit
25th day = Feb12: 42978 extrapolated from the fit
26th day = Feb13: 43977 extrapolated from the fit
27th day = Feb14: 44699 extrapolated from the fit
28th day = Feb15: 45214 extrapolated from the fit
29th day = Feb16: 45577 extrapolated from the fit
30th day = Feb17: 45830 extrapolated from the fit
31th day = Feb18: 46006 extrapolated from the fit

the top asymptote is 46399 (standard error of 1690) EDIT if the virus begins to spread from new sources, this model will become useless as a matter of course
 
Last edited:
Yesterday at 9:13 AM
I was wondering how much the supply chain would be affected, while reading
Factories in China should resume operations amid coronavirus fight: expert
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now inside
Resumption at Tesla Shanghai factory faces great challenge from virus control
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:


It would be hard to tell how much production capacity can be restored at Tesla's high-profile Shanghai plant without the support from its upstream supply chain.
 
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