The culprit: the FLiRT variants. This family of variants, which evolved from omicron, took off in the spring. Now, they account for over 50% of infections. According to Dr. Robert H. Hopkins, Jr., the medical director of the National Foundation for Infectious Diseases, this year’s summer wave got an early start ― and it doesn’t appear to be slowing down anytime soon. “I suspect it’s going to increase,” Hopkins told HuffPost. “It seems like we’re seeing more and more states showing increased levels of activity.” Here’s what to know about the summer COVID spike:

The FLiRT variants are offshoots of JN.1, which was the dominant variant in the U.S. this past winter. This family of variants appears to be very contagious, thanks to mutations in the spike protein that may improve the virus’s ability to bind to human cells. “When we look at their molecular profile, some of those mutations potentially could allow the [virus] to escape from previous immunity,” Hopkins explained.

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