So were the epidemiologists wrong about herd immunity and the USA has hit herd immunity at 50% vaccinated (plus natural infections, some of whom also got vaccin

So were the epidemiologists wrong about herd immunity and the USA has hit herd immunity at 50% vaccinated (plus natural infections, some of whom also got vaccinated)? I do not think we know what is going on right now, it is very strange that infections are receding in the USA. It is not due to weather, the USA South had spread last Summer while the NorthEast receded. We have been experiencing waves but it is not entirely clear what is causing them. 50% vaccinated is not enough to stop the spread so something else is. My theory is that there is much more asymptomatic spread than we know of and the waves are due to variants. Each new variant spreads and burns itself out till the next takes over. People who were naturally infected instead of vaccinated may be more susceptible to variants; what happened in the Saychelles may support that idea: https://www.channelnewsasia.com/news/commentary/covid-19-vaccination-seychelles-variants-pfizer-moderna-14856378 https://www.channelnewsasia.com/news/commentary/covid-19-vac... If that is not the cause of the waves, were the epidemiologists just wrong about herd immunity and we are already there? If variants are the cause of waves we could see another wave in the USA in several months as vaccinations taper off. I have not seen a good explanation for the waves yet. Some say people's behavior is the reason, but that can not explain what is currently happening in the USA.