The surgeon general is encouraging people to get vaccinated and warning about new variants of the coronavirus.
"For those who are unvaccinated, they are increasingly at risk as more and more variants develop," said U.S. Surgeon General Dr. Vivek Murthy.
About 15.5 million Americans would need to get a shot in the next four weeks to hit President Biden's goal of 70% of adults having at least one dose by July 4.
Fewer people are getting vaccinated each day. Almost 64% of adults have received their first shot. But reaching herd immunity also requires the youngest Americans get vaccinated.