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mNRA booster after 2 J&J vaccinations?

A friend of mine from another country is visiting the United States. I saw her last night and she told me that she has gotten 2 J&J shots. The second one was last week. I sent her a message last night saying that I have heard on the news that the J&J vaccine is not as effective as the mRNA vaccines and that I understood that the people who have gotten the J&J vaccination could get a second shot of Pfizer or Moderna. She wrote me back saying that she was concerned. Can she or should she pursue an mRNA vax? This would be the 3rd dose after a recent 2nd J&J dose. If she is to get another shot she must do it fairly soon since she returns home in mid-January. Vaccines are not easily or readily available in her country. Anyway, if you have any guidance on this situation, it would be most appreciated.


2 Answers

You need to wait a few weeks after the second shot before getting a booster. That gives you time to check out the pharmacies, hospitals and large medical groups in your area as to who has J&J and whether they will be willing to give her a different brand for her booster.
The CDC currently does NOT recommend another shot so soon after the J&J booster. Once someone has had TWO J&J injections(with the 2nd being very recent), the level of immunity attained will be significant and it is unlikely that getting a 3rd shot so soon after the 2nd will signifcantly increase her level of immunity. But, in 6 months or so--it is likely that another shot will be advised due to waning immunity and the fact that type of COVID virus will change. Thus, she needs to stay alert to future recommendations.
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