I'm about 110 pages through Clark's book and just finished his description of the plague. It didn't leave many frail disfigured survivors for the simple reason that it didn't leave many survivors, with death rates among the infected in excess of 75%.

Peter,

Of course, in an economic rather than physiological sense, it did leave plenty of "disfigured survivors": widows, orphans, poorly defended villages, etc.

Caplan's big claim is that almost anything that persistently raises death rates is likely to persistently reduce output per living worker. It that true?

One possible source of persistent increases in death rates that have no impact on productivity: Many kinds of infectious disease.

I'd welcome medically-informed comments on the topic, but it seems possible for infectious disease (from, say the bad sanitation that Clark emphasizes) to raise the chance of dying any given month without appreciably hurting your productivity most of the time.

Scenario: You get sick for a week or two every couple of years, and if you survive, you go back to being productive. If you don't survive, well then, you're pushing up the death rate.

My vague sense is that lots of infectious diseases are of the quick variety (dead or healthy within a few weeks) rather than the persistent and debilitating variety. Am I wrong about that?