It is necessary -- a fourth boost for right now.
The protection we are getting from the third is not that good against infections, but doesn't last very long.
https://edition.cnn.com/2022/03/15/healt...index.html
The protection we are getting from the third is not that good against infections, but doesn't last very long.
https://edition.cnn.com/2022/03/15/healt...index.html