Africa generally being a poorer continent also means a lot less travel to spread the disease, especially international travel from Asia and Europe, and the potential for local outbreaks to pass unnoticed due to lack of medical care, especially if symptoms for most young people are benign, and elderly people dying at the first sign of infection is a common occurrence

There could be less testing in Africa, so less confirmed cases. Here in New Zealand we have had only 5 cases with no increase in days, yet very close links to China and Australia and cool fall weather, making me wonder if and how many undiagnosed cases there are.

Best papers I've seen on the weather - virus link so far

https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3551767

https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3550308

The case fatality rate is estimated at 2% - 3% but that is with medical care. Without ventilators and ICU care, CFR might rise to as high as 10%-15%. With its exponential growth rate, it'd be highly surprising for the virus to go unnoticed so long.

I saw different numbers, ~0.6% with good medical care(SK), 2-4% with poor medical care (Early stages in China).

According to the Johns Hopkins doctor recently interviewed by Sam Harris (sorry, couldn’t find the name) the South Korean number is likely the more accurate one due to a higher prevalence of testing. The higher rates from other countries are essentially a denominator problem (I.e., with limited tests only the most sick are tested, leaving the only moderately sick untested and thus out of the calculation)

I've seen an infographic passed along, albeit on twitter, so authenticity is suspect --but it was comparing ages in SK and Italy of cases, where mortality is higher in Italy, because mean age was higher in Italy, a lot of the tests in SK were in churches where initial outbreaks were that were prevalently populated by youth...

2000x 20 year olds 2000x 60 year olds...and you're gonna have highly different results for CFR.

I'd say it's somewhere in the middle of both... maybe something like 1.5. But I'm not an epidemiologist, but if the age gaps matter then it could be about that... just my thoughts.

Do you have a source for the '10%-15%' value? If not, I'd encourage you to not spread FUD.

That's the estimated percentage of people who need some form of ICU treatment due to COVID-19. If there's no more ICU beds left, it's safe to assume that the majority of people in need of ICU treatment that can't get it will die.

You also have to add all the other patologies that will get affected by the lack of ICUs. All in all, 10% is a safe estimate. That's why flattening the curve is extremely important. The actual percentage in need of ICU will surely vary with time, but that's the important metric, because that's how many people will die when the health system saturates.

5% needing ITU was initial estimate. In Italy it’s 10% due to an elderly population. And some on ITU would survive without ITU but it does improve chances. You make good points, I’m mostly just saying there is a high degree of uncertainty

Multiple sources indicate that’s the severe percentage, and we know a bit about untreated ards.

Moreover, deaths from lack of capacity will not be limited to covid cases. And many of the current non-covid icu cases may be exposed to medical staff who are not being tested (in the USA) and die that way. This is what happens in nursing facilities like Seattle.

Italy is the first Nation that lost control of the virus and can't get infected into icu. Just look at their numbers for a real world example.

Yes, look at their numbers: more than 5000 ICU beds (and more being added) and less than 1000 in use.

https://www.linkiesta.it/it/article/2020/03/11/italia-corona...

https://www.washingtonpost.com/world/europe/italy-coronaviru...

https://www.newnotizie.it/2020/03/12/coronavirus-posti-letto...

the ramp up isn't done, nor halfway yet, as italy hasn't reached inflection of the exponential curve yet. once the net new cases begins to steadily decrease the numbers are roughly half way to the final max.

But AC is very common in the US too. So shouldn't we expect spread in US summer to behave more like Qatar than Africa? Europe on the other hand may slow down since I think AC hasn't caught on to the same extent.

It depends on the part of the US you live in. In Florida (where I am from) air conditioning is common. In Boston its only common in offices.

If he reduces spread, it will be helpful on the margin and may help flatten the curve

Demographics structure. E.g. in Nigeria 65+ old constitute ~3% of population, in Italy ~22%. Now compare that with COVID-19 severity and mortality age breakdown.

Source: https://www.cia.gov/library/publications/the-world-factbook/...

I thought that the reason cold weather helps the spread is the higher humidity means the water droplets you spray last longer.

Air conditioning tends to produce a very dry environment which should also cause the droplets to evaporate very quickly.

Cold weather weakens your immune system.

Also cold weather has lower humidity.