Merged 2019-nCoV / Corona virus

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Giordano said:
Do you know what is the actual evidence this is true? I realize that it was attributed to the Chinese government, which sounds very official, but the attribution appears to me to be a post by some unrelated dude. I’ve had trouble following this back to document an official policy.

What do you know about it?
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I've found the article in another forum. I hoped that you guys would know more about it. Seems like the only other site reporting this is
https://www.tagesspiegel.de/wissen/...china-meldet-mehr-als-1000-tote/25472332.html

But they too refer to this tweet.
https://twitter.com/lwcalex/status/1226840055869632512
 
Looking for that Tweet statement I found a confirmation in the Taiwan News:

China changes counting scheme to lower Wuhan virus numbers

I'm not sure changing the case definition was purely to hide numbers of cases. There are indications for the criteria for case definitions.
In a notice issued by China's National Health Commission (NHC) on Feb. 6, it wrote that the classification of new Wuhan virus infections will be divided into four categories: "suspected cases," "clinically diagnosed cases," "confirmed cases," and "positive tests." Among these, "positive tests" refers to "asymptomatic infected patients" who test positive for the disease but have no symptoms.
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It's common to include positive symptoms plus a positive lab test result in a case definition. It depends on the reason they are doing it. Maybe they are concerned about false positive lab tests. Maybe quality control in the testing is a problem.
There is also a clear stipulation in the official document stating that "If the reported 'asymptomatic infected patient' has clinical manifestations, their status shall be revised to 'confirmed case' in a timely manner" (highlighted text in Tweet below). This indicates that even if a person tests positive for the disease but does not exhibit any symptoms, they will no longer be included in the daily infection reports.
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There are possible reasons for this besides sinister ones. Not saying we can rule sinister out mind you. Just trying to keep an open mind.
 
Skeptic Ginger said:
India...
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Interesting with all the distrust of China, nobody's mentioned India, whose government recommends ayurvedic homeopathy to combat the disease.

That's a country whose government I wouldn't trust as far as I could throw the Taj Mahal.

When India admits there's a problem it will be far too late and Indians will have spread it far and wide. They are still admitting to only three cases, and I don't believe any of that.
 
The Atheist said:
Interesting with all the distrust of China, nobody's mentioned India, whose government recommends ayurvedic homeopathy to combat the disease.

That's a country whose government I wouldn't trust as far as I could throw the Taj Mahal.

When India admits there's a problem it will be far too late and Indians will have spread it far and wide. They are still admitting to only three cases, and I don't believe any of that.
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I know, right. Why’s everyone talking about China of all places?
 
carlosy said:
Source or sarcasm?
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https://www.sciencealert.com/india-...ending-homeopathy-to-ward-off-the-coronavirus

angrysoba said:
I know, right. Why’s everyone talking about China of all places?
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You might need a lesson in comprehension if you think in any way relevant to my post.

It's there in the plainest English and there's hardly a word with more than three syllables* - read it again and see if your response bears any relation to the reply you made.

*In fact, the only two words with more than three syllables are "ayurvedic homepathy" and they can both be put into one simple word with two syllables, one of which is "bull".
 
Meanwhile, the economic fallout is spreading internationally: https://www.bbc.com/news/business-51441344

(The fact that a certain American politician will use this as another reason to bash China is hardly even worth mentioning, so I won't mention it.)
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Couple of other interesting points:

Japan, with 163 cases has no severe cases. Yet.

Also, cases outside China are only listed as severe for 12 people out of 400 cases, a tidy 3%, against China's 16%, still raising the question of whether the virus is more virulent in 1st & 2nd generation infections. We can only hope, but time will tell.

The only place with exponential growth in cases is the cruise liner.
 
Just to give some rough figures for endemic seasonal flu.

Roughly 10% population get flu each year - 600,000,000 people. Of these approximately 1% will be severely affected ie need medical care 6,000,000, and 10% of these will die ie 600,000 global deaths yearly from flu, a 0.1% mortality rate. The problem with a pandemic flu strain is that nearly everyone gets infected over a relatively short time span (locally) so disruption is high and total mortality is higher.

Assume a population of 1,000 susceptibles in an epidemic with a 2% mortality (Perhaps what the 1918 flu was at its worst). You get 20 deaths. Move on a bit and you now have a population of 1,000 but 90% have had previous exposure to the circulating flu strain. Because of antigenic drift immunity is not absolute, people can still get flu but because of partial immunity the illness is milder, and they may be infectious for a shorter period. The virus also mutates, it becomes more virulent by developing a mutation that weakens the immune response. The mortality in the partially immune 900 is 1% with 9 deaths. In the susceptible 10% (100 persons) the mortality has risen to 4% with 4 deaths, a total of thirteen in the population as a whole. The virus can be both more virulent but total mortality fall when it is endemic rather than epidemic.

Papers I referenced above showed that endemic seasonal flu strains do acquire mutations associated with increased virulence. Mutations are random, there is no reason why mutations should be in the direction of decreased virulence.

In general increased virulence e.g. mutations aiding evasion of the immune response are associated with increased transmissibility. There is no natural law to say that viral infections become less virulent with time.

If we look at the current coronavirus, it seems to have a long prodrome during which it is infectious. After two weeks of spreading it is relatively unimportant in evolutionary terms whether the host lives or dies. Successful mutations will favour increased viral shedding (usually associated with increased virulence) and increased infectivity. This is why in the paper referenced above epidemics are expected to be associated with increasing virulence not decreasing virulence.
 
Planigale said:
Just to give some rough figures for endemic seasonal flu.

Roughly 10% population get flu each year - 600,000,000 people. Of these approximately 1% will be severely affected ie need medical care 6,000,000, and 10% of these will die ie 600,000 global deaths yearly from flu, a 0.1% mortality rate. The problem with a pandemic flu strain is that nearly everyone gets infected over a relatively short time span (locally) so disruption is high and total mortality is higher.

Assume a population of 1,000 susceptibles in an epidemic with a 2% mortality (Perhaps what the 1918 flu was at its worst). You get 20 deaths. Move on a bit and you now have a population of 1,000 but 90% have had previous exposure to the circulating flu strain. Because of antigenic drift immunity is not absolute, people can still get flu but because of partial immunity the illness is milder, and they may be infectious for a shorter period. The virus also mutates, it becomes more virulent by developing a mutation that weakens the immune response. The mortality in the partially immune 900 is 1% with 9 deaths. In the susceptible 10% (100 persons) the mortality has risen to 4% with 4 deaths, a total of thirteen in the population as a whole. The virus can be both more virulent but total mortality fall when it is endemic rather than epidemic.

Papers I referenced above showed that endemic seasonal flu strains do acquire mutations associated with increased virulence. Mutations are random, there is no reason why mutations should be in the direction of decreased virulence.

In general increased virulence e.g. mutations aiding evasion of the immune response are associated with increased transmissibility. There is no natural law to say that viral infections become less virulent with time.

If we look at the current coronavirus, it seems to have a long prodrome during which it is infectious. After two weeks of spreading it is relatively unimportant in evolutionary terms whether the host lives or dies. Successful mutations will favour increased viral shedding (usually associated with increased virulence) and increased infectivity. This is why in the paper referenced above epidemics are expected to be associated with increasing virulence not decreasing virulence.
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Not to detract from what you are saying but one reason flu is less virulent is because governments have national campaigns to get the over-65's and health-problem groups vaccinated against the various strains forecast in advance by the experts.

Secondly, coronavirus is not flu. (I note some of the national papers are calling it flu, too.) It is part of the cold family.
 
Vixen said:
Not to detract from what you are saying but one reason flu is less virulent is because governments have national campaigns to get the over-65's and health-problem groups vaccinated against the various strains forecast in advance by the experts.

Secondly, coronavirus is not flu. (I note some of the national papers are calling it flu, too.) It is part of the cold family.
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Apologies I am not making myself clear.

Virulence is an intrinsic property of the virus. Public health interventions such as vaccination do not effect virulence. The consequence of infection will be morbidity and mortality, this will be an interaction of host, pathogen and environment; vaccination will impact mortality and morbidity. I am trying to explain why mortality can fall despite viral virulence increasing.
 
And... the official, non-offensive, World Health Organization name for the virus is now...

[drum roll]

COVID-19 (the article also mentions Covid-2019, but I think that's a mistake).

https://www.bbc.co.uk/news/world-asia-china-51466362

The acronym stands for 'Corona Virus Disease' with the last two digits of the year of its appearance appended after a hyphen.
 
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Disease. I edited my post above to correct the BBC's errors, and include what the acronym stands for.
 
Planigale said:
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Papers I referenced above showed that endemic seasonal flu strains do acquire mutations associated with increased virulence. Mutations are random, there is no reason why mutations should be in the direction of decreased virulence.
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Funny, other than mild differences, we don't see that happening. Care to cite a strain of seasonal flu that happened to that wasn't from a reassortment?


And no, your cites didn't say seasonal flu mutates to more severe cases. Your sources were about genetic changes in general, basic evolution we all know: selection pressures acting on random mutations.

Also, what are the selection pressures that act on seasonal flu to produce more virulent strains? You seem to have forgotten that half of the equation.
 
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Vixen said:
Not to detract from what you are saying but one reason flu is less virulent is because governments have national campaigns to get the over-65's and health-problem groups vaccinated against the various strains forecast in advance by the experts.

Secondly, coronavirus is not flu. (I note some of the national papers are calling it flu, too.) It is part of the cold family.
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There is no "cold family".
 
The Atheist said:
Meanwhile, the economic fallout is spreading internationally: https://www.bbc.com/news/business-51441344

(The fact that a certain American politician will use this as another reason to bash China is hardly even worth mentioning, so I won't mention it.)
____________________________

Couple of other interesting points:

Japan, with 163 cases has no severe cases. Yet.

Also, cases outside China are only listed as severe for 12 people out of 400 cases, a tidy 3%, against China's 16%, still raising the question of whether the virus is more virulent in 1st & 2nd generation infections. We can only hope, but time will tell.

The only place with exponential growth in cases is the cruise liner.
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There are ways to do a quarantine correctly... and ways to do it wrong. It is hard not to suspect that the cruise liner Diamond Princess did it wrong. To give them the benefit of the doubt there is the possibility that enough passengers infected one another (135 so far) during normal ship events before the quarantine/stay in your cabins was put into place. In this case the current cases were already infected and the quarantine may have in fact prevented others from being infected. But the pattern of additional infections increasing day by day must either be due to the known different incubation periods or to fundamental flaws in the design and implementation of the quarantine.
 
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