[hyperpape]

Depends on what you're comparing. I agree we can't assume that the rest of the country will see similar infection rates. However, it's less clear to me that fatality rates would be incorrect.

On the other hand, there's one very specific way that considering NYC gives us data we can't (yet) get elsewhere. While it's possible that we're underestimating disease prevalence by 50x elsewhere, it's basically impossible in NYC (almost 2% of people already have tested positive, with less than 10% of the population being tested).

[makomk]

Note that the test NYC is using only tells you whether the person has Covid-19 at that point in time, so it's entirely possible to test even 100% of the population and still substantially underestimate disease prevalence if you tested most of them at the wrong time (which you probably would!)

[smsm42]

> However, it's less clear to me that fatality rates would be incorrect.

Depends on whether mortality rates can be variant on environmental conditions, such as viral load, population density, access to healthcare/ICUs, population socio-demographic profile, etc.

[hyperpape]

These are good points, and I think I ended up claiming a much stronger claim than I should've. There's plenty of reasons NYC could have a higher death rate than elsewhere. I don't know how precisely you could estimate the potential death rate from just NYC's data.

What I would still say is that it's reasonable to say "NYC has .18% of its population dead. It's extremely implausible that this disease is no more lethal than the flu is, when that's 10x the overall death rate from the flu. If you present me evidence suggesting that from elsewhere, it's going to have to be quite strong to overcome the evidence from NYC."

[weaksauce]

the flu would be way more deadly than it is if there wasn't a seasonal flu shot that gives herd immunity.

edit: it shouldn't be controversial to say that a thing that kills 30-80k per year with active measures of mitigation already something that would be more deadly without a vaccine. seriously reflect on that. the corona virus is something we need to take 100% seriously but also acknowledge that the flu is also very deadly... even more so without any mitigation (thankfully we have for the common flu)

[arcticbull]

The flu probably wouldn't be dramatically worse if we didn't have a vaccine. The vaccine isn't particularly effective all things considered, ranging from 10% to 60% depending on the year and how well scientists were able to guess which strain would be predominant.

The flu as-is causes 45,000,000 sicknesses every year in the US alone.