A recent letter writer in the Tribune may not be aware that whole countries are vaccine hesitant. Countries from New Zealand to Vietnam controlled the spread from the start and may yet see the same end — another circulating or endemic pathogen that emerged from wet markets — but not before immunocompromised residents are protected. Vaccines are nice to have in the medicine kit but slow, expensive and inefficient in the crisis phase.
A number of experts in the field have noted that estimates of population immunity (aka herd immunity from agriculture and veterinary medicine) are now about 34 percent from natural infections and 43 percent from vaccines, adding that we are therefore approaching 60 percent. Evidently, pandemic surveillance data show many people with natural immunity are getting vaccines, which helps explain why the numbers are not strictly additive.
We know many people are infected, generate an immune response and experience mild or ambiguous symptoms. These populations are estimated from figures other than hospital admissions and may be even less reliable. They are likely to be more “strictly additive,” so we could be well above 60 percent.
Population immunity is generally estimated to be “effective” between 60 and 80 percent. It is connected to the R number, which is clearly below zero and trending in the right direction almost across the board in California. The R number is also less speculative compared to the estimate for population immunity: https://ca-covid-r.info/
Case data and the weight of the epidemiological evidence combined with hospitalization rates don’t support turning to examples from other countries with very different experiences and systems. The U.S. let the virus spread initially, effectively guaranteeing tremendous cost to human life from community spread.
It’s pretty clear that mass vaccination taken to extremes would stigmatize immunocompetent adults needlessly at this point.