Superficially regarding number 2: on a population scale a lot depends on how contagious the disease is. The measles vaccine is very efficient (over 95% after tw

Superficially regarding number 2: on a population scale a lot depends on how contagious the disease is. The measles vaccine is very efficient (over 95% after two doses), but still requires something like a 90% vaccination grade to prevent outbreaks. Measles is very very very contagious. Covid is not nearly as contagious, so to prevent outbreaks it doesn't have to be nearly as good at the same vaccination grade. For an individual, however, 70% would not feel very reassuring, which is why we need a lot of people getting vaccinated. Edit: fixed some autocorrect issues. I feel I should add: measles is not at fun, even if you don't have any complications. You become very sick. Serious complications are _a lot_ more common than adverse reactions to the vaccine. Don't rely on other people being vaccinated unless you have a compromised immune system in any way.