I'm from Pennsylvania originally, and one of my friends from back home was asking yesterday why the state was taking such draconian measures when only 300-some people had it. Why kill the economy for a few hundred sick people? I ran some numbers to try to explain. 
Over the past week the # of people who've tested positive in PA has increased by 7X. If it continued to spread at that rate (and there's no reason to believe it wouldn't unless significant mitigation measures were taken, & based on what's happened elsewhere) then that means...
By 3/29 there would be about 3400 cases in PA
By 4/5 23,800 cases
By 4/12 166,600 cases
By 4/19 1.1 million cases
By 4/26 (a bit over a month from today) there would be almost 8 million Pennsylvanians who'd contracted Covid-19. That's > 50% of the state population.
By 4/5 23,800 cases
By 4/12 166,600 cases
By 4/19 1.1 million cases
By 4/26 (a bit over a month from today) there would be almost 8 million Pennsylvanians who'd contracted Covid-19. That's > 50% of the state population.
In sum, going at its current rate of expansion, Covid-19 would infect the majority of Pennsylvanians by the end of next month if no abatement measures were taken.
According to this article there are 3400 ICU beds in PA. If 8 million people get Covid-19, assuming 10% need ICU care (which is the rate we've seen in other countries), then that means PA would need 800,000 ICU beds to meet the demand in this coming month. inquirer.com/health/coronav…
To repeat, there are 3400 ICU beds in the state of PA right now. That would be a shortfall of 796,600 ICU beds in this scenario. And this is just one state which comprises less than 5% of the US population.
So if you know someone who is pooh-poohing this and saying "there are only a few hundred people with it right now," please give them a tutorial on how exponential growth works.
This seems relevant here.
To be clear, all I did here was basic math and basic biology using existing data. I have no special insight into or expertise about this apart from that. I just thought that my mode of trying to explain this to a doubting friend might be of use to folks out there.
I found this site, designed by people who are actually experts on this stuff, to be edifying...and also terrifying...and also clear evidence that we need to act asap (and should have done so much earlier). covidactnow.org/state/PA
