What will happen in the US in the next few months with the #coronavirus? Unknown, but let's make a few guesses.

If the US ends up following a Herd Immunity strategy, it might end up with between 800k and 3.5M deaths. Will it though? (thread) [1/

It looks like the infected fatality rate (IFR) is ~0.5% to 1.5%
https://medium.com/@tomaspueyo/coronavirus-should-we-aim-for-herd-immunity-like-sweden-b1de3348e88b
[2/

Also, it looks like ~50% to 80% of the population could eventually be infected.

(R is ~2.7 so far, but some reports that a new strain is more infectious and could have an R as high as 5. Assuming some heterogeneity, let's leave it at 50%-80%.) [3/

https://github.com/midas-network/COVID-19/tree/master/parameter_estimates/2019_novel_coronavirus

So that's a total of 0.25%-1.2% of the US pop dying, or between 800k and 3.5M.

Let's check that with another country farther into the Herd Immunity strategy: Sweden [4/

Sweden has 5k official deaths so far and ~10M population, so right now the overall #coronavirus mortality rate (deaths/total pop) is 0.05%. Apply that to the US population, and you get ~160k deaths (so 50k more than today) [5/

But we know by end of April they just had ~5.4% of the population infected. Let's assume they have by now 10% of the population infected. It means cases will still 6x until HI (~60%). Deaths will also likely 6x. That's a total of 30k deaths, or 0.3% of the population. [6/

If ~0.3% of the US population dies of #COVID19 , that's ~1 million deaths. We're still in the same range as before. [7/

That assumes the US goes for Herd Immunity till the end. Will it? Maybe. Things are evolving by the minute, and this is an election year, which can change everything. So the question is: What will US politicians do in the next few months? [8/

Right now, a bunch of states are past the 1st wave, such as MT, HI, NY, VT, or NJ. A few are in the 2nd wave, such as GA, WV, FL, TN, KY. A few never left the 1st wave, such as CA, AL, NC, SC. [9/

The Federal level has decided not to mandate anything. It's likely to continue this way. This leaves the decision on the 50 states, which behave a lot like 50 independent countries here. [10/

States like TX, GA or FL are opening up despite being in historic maximums of cases. It doesn't look like it's stopping them, and the virus will likely spread. Will they stop? What could change their minds? [11/

Maybe pictures of a collapsed healthcare system. That worked the 1st time around. We will soon see: Arizona is might soon hit capacity. Will it correct its course then? [12/
https://covidactnow.org/us/az?s=49762 

If they do, there's hope the other states will do too. That will be good, because it will prevent lots of deaths. If they don't correct their course, that's a signal that these states will go for herd immunity. [13/

Note that we don't need to go back to lockdowns to stop the virus. Now we know what works: masks, testing, contact tracing, isolations, quarantines, hygiene, physical distancing, public education, travel restrictions and gatherings restrictions [14/

If some states go for herd immunity, the question becomes: What will others do? AK, OH or CA, which have been fighting heavily, will they let their efforts go to waste by importing cases from other states?Or will they quarantine incoming travelers and enforce it, like HI or AK?

CA is especially interesting. They are fighting hard, but aren't winning yet. The Latino community has been hit harder—which echoes what is happening in LatAm. They might have fewer work-from-home jobs. The Central Valley is also suffering. [16/

So will CA keep fighting and adapting its tactics? Or will it give up? If other states like neighboring AZ have massive outbreaks, will they request a quarantine for travelers? Give up? Or neither, and keep tirelessly working to defeat a virus that keeps being seeded? [17/