Researchers looked at the data of almost three million South Africans who were previously infected with Covid-19 to see whether the risk of getting reinfected has changed with the arrival of the Beta, Delta, and Omicron variants. They found the Omicron variant is linked with a “substantial ability” to evade the immunity built up from a prior infection, while there was no such evidence of the Beta or Delta variants doing so.
This is a companion discussion topic for the original entry at https://www.sciencemediacentre.co.nz/2021/12/03/previous-covid-19-infection-may-not-protect-against-omicron-expert-reaction/