We now have the first hard data from regions that achieved “herd immunity” the hard way – that is, by having Corona burn through most of the population.
70% of blood donors from Castiglione d’Adda, in the 50,000 population region of Lodi, the epicenter of Italy’s outbreak, tested positive for SARS-2 antibodies.
There’s just one very minor problem*:
ROME — One of the latest deaths in Italy’s coronavirus crisis is the father of a young man known as Italy’s Patient No. 1.
Italian state TV said the father was one of 62 deaths so far in the outbreak that have occurred in Castiglione d’Adda, one of 10 Lombard towns which were the first to be put on lockdown in northern Italy.
According to Wikipedia, the population of Castiglione d’Adda is 4,659. This makes for a mortality rate of 1.3% and that’s based on numbers from March 21!
For comparison, the Italian crude death rate is 10.7/1,000. That’s the annual figure. Crudely projecting onto Castiglione d’Adda, that’s about 50 expected deaths per year. That’s what COVID-19 accomplished in just a month – an effective doubling of the yearly mortality rate.
By extension, these figures would translate into 327 million * 1.3% total mortality = 4.35 million EXCESS deaths in the US in one year (well more than a doubling of its usual rate!).
And that’s leaving aside for now that some Corona-related deaths in Castiglione d’Adda have yet to occur!
* I have also seen figures in the range of 40-45 deaths Castiglione d’Adda. This is not as bad, but still wouldn’t change anything on the order of magnitudes – not that we can get any more precise than that, anyway.