Ultimately, the committee only recommended the vaccine to be used seasonally—between September and January to protect babies born between October and March, when RSV transmission typically peaks. (There is an exception for pregnant people who live in an area of the US where RSV circulates year-round, such as Hawaii and Gaum.)

U.S. health officials are recommending RSV vaccinations for moms-to-be as a second option to protect newborns.

CDC is recommending the shot for people who are between 32 and 36 weeks pregnant and will give birth during the fall and winter, when RSV cases usually spike.

Pregnant people should get an RSV vaccine from Pfizer that transfers antibodies to their babies, according to a new CDC recommendation. It's the first RSV shot of its kind.