Today it appears that you can get get it twice and the second time it can be worse, this needs far more investigation before proven as fact.
https://www.independent.co.uk/news/...-cases-latest-study-vaccine-b990859.htmlFor the purpose of discussion, let’s assume it’s true. How does herd immunity work if the herd keep getting it and it gets worse each time they contract it eventually the herd dies out.