Why COVID-19 Deaths Aren’t The Best Measure of Flattening the Curve
You might have noticed a contradiction: Everyone is saying that the curve is flattening, yet the death rate in the U.S. shot up yesterday. This might make it seem like it’s not working.
Relax. (Okay, it’s terrible, but…)
Why the Death Rate Isn’t a Good Early Indicator
The incubation period of COVID-19 is 2 to 14 days with occasional outliers. The average is 5 to 6 days.
The typical period from symptom onset to death seems to be about two weeks.
So, people who died yesterday could have been exposed a month or more ago. The fatality curve is going to lag the case curve by about two weeks (all of this has a lot of variation, but we’re sadly dealing with fairly large numbers here.
What Should We Look at Instead?
The primary thing public health people are looking at is new confirmed cases per day.
If we look at that for New York, then the number of confirmed cases (and that’s with improved testing) peaked on April 4, with a second lower peak on about April 8. It’s declined since, although it’s a ragged chart with peaks and valleys. Fewer tests are being processed on weekends and different places are counting cases on different days (symptom onset? Date the test was performed). But again, we’re dealing with fairly large numbers here, which should smooth out these to some degree.
The other number that is harder to get is new hospitalizations. This is a key number for controlling the burden on health care facilities and workers.
Unfortunately, I haven’t found anyone publishing these charts, but Cuomo has said that hospital admissions are distinctly slowing in New York. We’re on the winning side when discharges exceed admissions.
When Can We All Go Outside?
Experts differ…with some saying we should live like this until there’s a vaccine (some time in 2021 or even 2022).
Widespread testing is needed, and reliable treatments to reduce death rates and keep people out of the hospital (and in it for longer).
The CDC plan to reopen the country is for a phased reopening that will start in early May, but in truth it’s going to be down to individual governors to make the best situation. Here in Virginia, we have a stay at home order through June 10, but Northam has cautiously hinted that he hopes to lift it sooner.
I’m not going to make a guess of my own because I don’t want to be wrong, but we won’t be back to “normal” for a while. Expect to be wearing masks in crowded places. Expect large gatherings not to restart until probably 2021 (sorry to those going to something that was rescheduled until the fall). Air travel will probably involve temperature guns before boarding.
And we all will have to show community responsibility. All of us.
Oh, and wash your hands.