[yakshaving_jgt]

Western news media are currently reporting ~100 dead and ~4,500 infected (though that number is surely much higher in reality). This is a ~2% mortality rate.

Can we naïvely extrapolate that we expect ~4,000 casualties from ~190,000 infections?

I'm not good at understanding numbers, but I'm sure someone here can chime in with a better way to read this.

[jerf]

You can naively extrapolate that, but it will be, well, a naive extrapolation. Not necessarily a bad thing, but it won't necessarily be accurate. If the virus does get into, say, the US, but it happens to only infect 20-40 year-olds through office transmission, it probably won't even be that fatal. If it happens to get into a senior home, it could be a great deal more deadly.

And that's before we consider the spoiler of mutations, which is the real problem. In the long term, it is evolutionarily advantageous for the virus to become less lethal and eventually fade into the background as just another cold, if it isn't wiped out by aggressive quarantining. However, in the short term, many of the same things that will make it more transmissible, such as more effectively converting host systems into virus factories, or contrariwise, being more effectively hidden while still being contagious, will also make it more dangerous to the host and/or society.

But for all that, there is a sense in which the "naive extrapolation" is also the best thing we have right now based on available data. It is, at least, data-driven.

[bildung]

I'm not qualified to have an opinion on the the virus, but the numbers could exhibit a selection bias: People with relatively mild symptoms and no death probably could be misdiagnosed as having a flu or proper influenza, which would imply that the mortality rate would actually be lower.

[sliken]

See: https://www.thelancet.com/journals/lancet/article/PIIS0140-6...

From the above URL, among 41 people who went to the hospital:

  * All 41 patients had pneumonia with abnormal findings on chest CT

  * acute respiratory distress syndrome (12 [29%])

  * RNAaemia (six [15%])

  * acute cardiac injury (five [12%])

  * secondary infection (four [10%])

  * 13 (32%) patients were admitted to an ICU

  * six (15%) died

So among those that were able to get to a hospital 15% died.

Question is what percentage of people exposed get bad enough to want to go to the hospital?