@trendless “Herd immunity” is being misused. It is “how much of the population needs to be vaccinated so that those who refuse or can’t are an insignificant number and the illness is stopped. “
For instance, “herd immunity against measles requires about 95% of a population to be vaccinated. The remaining 5% will be protected by the fact that measles will not spread among those who are vaccinated. For polio, the threshold is about 80%.”