Originally posted by d000hg
View Post
R is affected by:
Transmissibilty
Opportunity
Duration of infection
Susceptibility in the population.
Of these, only opportunity and susceptibility can be tackled. The former through measures such as lockdown and social distancing. The latter through vaccination.
The percentage of people who need to be vaccinated for herd immunity is 1-1/R. So if R is 4, then 75% need to be vaccinated. If it is 18 (measles for example), 95% need to be vaccinated. And that's assuming a 100% effective vaccine.
So yes, sure, beyond a certain point it won't make a difference. But that point is rather high.
Comment