Quote from: Cnut237 on March 23, 2020, 09:10:51 PM

Quote from: PrimeNumber7 on March 22, 2020, 02:51:29 AM

Coronavirus is very contagious. If you have coronavirus, you will possibly have it for weeks before you start showing symptoms, and you may be contagious for days before you show symptoms. It is estimated that coronavirus will kill between 1 and 3% of people who contract it, however between 15 and 20% of people will require critical medical care, including those that will die from it. If you need critical medical care, but do not receive it, the chances you will die from coronavirus is almost certain. This is why it is so important that the coronavirus not spread quickly.

Whilst it's certainly a serious problem and absolutely should be treated as such, I'm not yet convinced by the mortality rates. Testing is often only performed for people exhibiting severe symptoms. We have the stand-out case of Germany, with 29,056 cases and 118 deaths (0.4%) which surely is due in part to the fact that they are conducting a huge 160,000 tests per week, and so picking up carriers with mild symptoms or who are asymptomatic... carriers whom other nations are likely to miss. Of course there may be other reasons; it's too early to make definitive assessments, but still, this seems a likely explanation.

Globally, the mortality rate is about 4.4%, and is around 1.4% in the US, which is fairly low on the spectrum. The mortality rate in Germany is something closer to 0.5%. By comparison, about 1.3% of the population dies every year, based on the average lifespan of about 72.6 years.

I think most likely the world population will need to develop herd immunity to the Chinese coronavirus. I don't think it is realistic to stomp out the outbreak via quarantines which involves shutting down the world economy. I believe the up to 14 day incubation period is too long, and the chances of being contagious but only having mild or no symptoms is too high. A vaccine is a year away, at best, but there may be a way to treat cases for those who fall ill.

You are correct, we do not know how dangerous the virus actually is among the general population, but we do know it is very contagious and contagious enough that absent preventative measures, the majority of the population will contract the Chinese virus. It takes at least 60% of the population to have immunity in order for herd immunity to develop. If the number of unknown cases is 95% of total cases, the mortality rate in the US drops to 0.07%. If we can figure out who is most likely to have zero or very mild symptoms, and take steps for this group of people to get infected while protecting the rest of the population, this number may go down if the predictions are correct.

The above mortality rate assumes that people who need care are able to receive care at the same rate they are today. If the number of current cases goes up, the number of people who need care will also go up. There is a limited number of additional "need medical care" cases the hospital system can handle (including additional capacity via the military). Most of the "need medical care" cases will survive, but only if they receive medical care. If the medical system gets overwhelmed, the mortality rate will spike, possibly to numbers above what the "known" cases reflect.

If the economy stays closed for too long, the economy will be destroyed, and millions of people will possibly be stuck in poverty. This in itself could result in a lot of additional suffering, negative medial outcomes, and death.

It is unclear why death rates vary so widely from country to country. This may be due in part to testing/reporting, but there may be additional insights to this.