The scientist, Dr. Fiona Havers, told colleagues at the Centers for Disease Control and Prevention on Monday that she no longer had confidence that the COVID and RSV data would be used "objectively or evaluated with appropriate scientific rigor to make evidence-based vaccine policy decisions," according to an email seen by Reuters.

There was a notable absence last week when U.S. Health and Human Services Secretary Robert F. Kennedy Jr. announced in a 58-second video that the government would no longer endorse the COVID-19 vaccine for healthy children or pregnant women.