The latest virus puzzle

Tyler Cowen writes,

many of the herd immunity theorists strike back and ask “where are the deaths“? But that is not the right question for testing herd immunity claims. Those claims were about transmission slowing down, and those claims should be true about Covid-19 cases whether or not more people are surviving in the hospital.

Why are cases spiking but deaths not spiking? Here is a set of hypotheses, in my subjective order of likely importance.

1. The strains that are circulating are less deadly.

2. The people who are getting it are less frail. See the discussion of “dry tinder” in Daniel Klein’s essay. And also enough folks finally got the memo about protecting people in nursing homes.

3. The treatments people get now are helpful, whereas six months ago they were ineffective/harmful.

4. Testing protocols are finding more of the milder and asymptomatic cases that they were missing before.

5. The long and variable lag between cases and deaths has become longer and more variable.

And note that the average daily death rate still stands above 700, which is outside of the range for a normal flu, at least on an annual basis.