When vaccines first became available, if you got Pfizer, you stuck with Pfizer. If you got Moderna you stuck with Moderna. At least, that’s what the leading medical advice was, though that didn’t stop some people from doing their own mix-and-match approach. Most people were content to have whatever vaccine they could get in hopes of putting a stop to the pandemic and ushering in a return to public life.
Now, it appears the medical advice is catching up with those early experimenters as more and more data pours in. Following its approval of boosters of the Pfizer vaccine for especially vulnerable Americans, the FDA is set to approve a third dose of Moderna and a second dose of Johnson & Johnson for those same categories of people (those 65 and older, those with underlying medical conditions, and those with high-risk jobs that require a lot of in-person interaction).
Considering the Pfizer and Moderna mRNA vaccines have proven more effective than Johnson & Johnson’s viral vector shot, allowing a mix-and-match regimen likely will boost protection better for people who initially got J&J. It will also make it easier for people to get a booster as soon as possible rather than having to wait for an appointment and availability for the vaccine type they got originally. Given all that, it is expected the FDA will also officially sanction mix-and-match for those getting a booster shot, and when the U.S. allows international leisure travelers to enter the country starting Nov. 8, those who have taken a mix-and-match vaccine approach will be approved.
The National Institutes of Health released a study last week showing that there is little chance of harm from mixing and matching and that there will still be high efficacy in preventing severe disease and death given that all three vaccines have shown good results.