danubis2 at 2024-03-21 16:07:02+00:00 ID: kvwmsrr

https://ccdd.hsph.harvard.edu/2020/12/17/covid-19-vaccines-and-herd-immunity/

Highlights:

When a new infection enters a fully susceptible population, as SARS-CoV-2 infection did in early 2020, each infectious case on average infects R0 other cases... At some time t when the disease has been spreading for a while, the average case in a population will infect R(t) others in that population, where usually R(t) < R0, thanks to the combined effect of immunity to infection that has accumulated, and control measures...Vaccines can help reduce R(t). We often refer to a critical vaccine coverage f*, which is the proportion of randomly chosen individuals in the population that must be vaccinated to achieve R(t) < 1. If we have a vaccine that reduces transmission by a factor x, then we want to create the situation where Rvac(t) = (1 – xf*) Runvac(t) = 1 — that is, where the average case in a vaccinated population infects less than one additional person...

Tldr: vacciner giver sjældent immunitet, men mindsker blot risikoen for at blive syg. En høj vaccine tilslutning forkorter epidemisæsonen for alle, og formindsker derfor risikoen for at blive syg for alle.