We're also about to discover what happens when people don't exercise their immune systems for 2 years. There's a "super cold" of some sort going around in the U

We're also about to discover what happens when people don't exercise their immune systems for 2 years. There's a "super cold" of some sort going around in the UK [1] which, while not COVID (and therefore is probably not vaccine-sensitive wrt vaccines designed for COVID), has similar symptoms and is a lot more severe than a normal cold. Normally you'd get colds 2-3 times a year (there are over a billion cases per year in the US alone), sometimes without noticing. These would "boost" your immune system from time to time and afford some limited protection against severe disease. That did not happen over the past 18 months for a lot of people, especially in countries like UK/NZ/Australia which went way overboard on lockdowns, to the point where there was no "flu season" last year. I bet US will fare better just because enforcement is relatively lax, and 190M people already had COVID [2] (probably due to not really observing any lockdowns or whatever). [1] https://www.bbc.com/news/newsbeat-58624295 https://www.bbc.com/news/newsbeat-58624295 [2] https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/burden.html https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/burd...