Didn't Everyone Develop Immunity In The First Wave?

Before the virus had the chance to mutate.

https://us.cnn.com/2021/04/23/india/india-covid-modi-government-intl-hnk/index.html

If not.

Someone's sold them an absolute lemon there.

https://www.rt.com/news/521829-africa-cdc-vaccines-expiry-date/