Thread on how COVID plays out in hotspots.

Look at Italy, UK, Belgium, USA. The USA looks very different.

However, when we examine the US as composed of many different “countries”, a different pattern emerges.

@ASlavitt @choo_ek @Rfonsi1
http://91-divoc.com/pages/covid-visualization/

Thread 1/

Now look at the US as if it is composed of a few individual countries.

Northeast which was worst hit in March/April starts to look like Italy, Belgium, UK.

The West and South are behaving like countries where COVID is just now taking off; they are yet to peak.

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When we look at individual big Northeast States as individual “countries” they start to resemble European hotspots, Italy, Belgium, UK.

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On the other hand, places in the US that are active now look very different. Yet to peak. And we don’t know how high the peak will be. Or how long it will last. Or how many lives will be lost.

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Almost everywhere COVID has raged, it has cratered. But it looks like almost every place has to peak first.

COVID has caused a lot of devastation & loss of life in every hotspot. But why does it crater? Is is because all these places took preventive measures? Masks?

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Or is it because that’s the extent of the susceptible population?

Will there be a second wave in hot spots as they reopen? Or won’t there be?

Looking at places which did no changes, and no incremental precautions, such as Peru, is intriguing.

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The Oxford group is not able to pursue the vaccine study because they don’t have enough COVID in the U.K.!! They are looking to Brazil and Africa. @ASlavitt

Is this the natural history of hotspots?

Does every place have to peak before they crater?

https://www.google.com/amp/s/www.cbsnews.com/amp/news/coronavirus-vaccine-trial-oxford-expands-south-africa-brazil/

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China is a geographically large country but has a different pattern than us. We dont see new hot spots outside of Hubei emerge. Possibly because using strict measures, China has made COVID an external threat. But risk remains. If they let COVID into the country from outside.
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One thing that is striking is that hotspots crater after only a small % of the total population has symptomatic COVID, and only a small % have even evidence of exposure by serology. This is what we need to really study. This is a big unanswered puzzle.

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I’ll make a bold (but hopeful prediction): Major hotspots like NY, Wuhan, Lombardy, may have 2nd waves. But even without a vaccine, I don’t think the magnitude of the second wave or loss of life will be anywhere close to the first.

But this doesnt mean we relax precautions

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We still absolutely need the fundamentals: Testing, tracing, universal masks, avoid indoor crowds, social distance as much as possible, hand hygeine.

Coz COVID is so dangerous that even if a small % of a state gets it, it will wreak havoc & lead to unbearable loss of life

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Thanks to @subatomicdoc for pointing me in the direction of http://91-divoc.com/pages/covid-visualization/
By @profwade_

One caution is the 2nd wave in Iran. Is it so high because the 1st one never dipped to baseline, or is that due to relaxing precautions too soon? It is something that supports NY, NJ, PA who want to be careful and not let virus back in from hotspots. https://www.google.com/amp/s/www.businessinsider.com/iran-second-wave-coronavirus-cases-botched-response-2020-6%3famp

One important point is countries, states, and places that didn’t become hot spots and controlled COVID well are at risk of becoming hotspots if they are not careful, because the susceptible population has not been exposed at all. So they too need to be extra careful.