J&J Efficacy drops precipitously from Mar to Aug, down to 3%. Suspected due to a combination of anti-body decline and delta.
FDA Advisory panel recommends a booster for all J&J recipients (at least two months after initial dose).
Looks like J&J was really a two-shot deal all along. Not a big deal in the US, the vast majority of people here got one of the mRNA vaccines.
https://www.cnn.com/2021/10/16/healt...day/index.html