The sudden nature of the “Spanish” flu pandemic meant that children born just months apart experienced very different conditions in utero:
In particular, children born in 1919 were much more exposed to influenza in utero than children born in 1918 or 1920. The sudden differential to the 1918 flu lets Douglas Almond test for long-term effects in Is the 1918 Influenza Pandemic Over?
Almond finds large effects many decades after exposure.
Fetal health is found to affect nearly every socioeconomic outcome recorded in the 1960, 1970, and 1980 Censuses. Men and women show large and discontinuous reductions in educational attainment if they had been in utero during the pandemic. The children of infected mothers were up to 15 percent less likely to graduate from high school. Wages of men were 5–9 percent lower because of infection. Socioeconomic status…was substantially reduced, and the likelihood of being poor rose as much as 15 percent compared with other cohorts. Public entitlement spending was also increased.
Jesus Christ our Lord and Saviour…
Repeat after me: CORRELATION DOES NOT EQUAL CAUSATION.
There are any number of things that could actually be causative factors, here: One would be the economic effect on the birth cohort from around the Spanish Flu epidemic that derives simply from having been born during the time that a huge chunk of the population was eliminated. Have a meteorite hit and do the same damn thing, and you’d probably see similar downstream effects on the kids born during the affected period simply due to things like dislocated supply chains causing problems with pregnant mothers getting enough of the right foods. Some secondary effect of the Spanish Flu epidemic could just as well be responsible for this set of statistical facts as the influenza itself. Using this data to try to extrapolate over into COVID-19 is just irresponsible scare-mongering–Hell, the actual effect of this on the currently fetal could just as well be positive as inimical, with the widespread isolation and lowered stress on the mothers being good for the developing fetus, or the stress of being isolated and afraid due to listening to idiots like this and in the media causing the poor little nascent kiddies to be bathed in a mass of stress hormones while mommy is freaking out.
Just because you can statisticalize some BS does not mean you should, let alone that you should broadcast the ephemeral speculations your dive into the data has produced. If you can draw direct connections, fine… But things like this? Shut the hell up. Looking over how they got these numbers, I see nothing that really indicates a real and identified causative factor, just that kids born during times of stress didn’t do as well as kids who had idyllic fetal and life experiences.