The bad news? Against these new subvariants, vaccines and prior infection are proving less and less effective at preventing infections and reinfections. They also appear to be at least somewhat less effective at preventing hospitalizations as the coronavirus evolves — particularly among the many un- and under-boosted seniors. A big wave of cases will be at best disruptive, will increase the risk of a lot more people developing long COVID, and will give SARS-CoV-2 many more opportunities to evolve. The impact of multiple COVID reinfections, which many Americans already have or soon will experience, remains unclear. Most importantly, BA.5 may be the worst COVID variant yet. Its unique mutations make it the best equipped major variant to date at avoiding antibodies, which means it can likely reinfect people who recently had other Omicron subvariants. There is still a lot that scientists don’t know about the strain, and the threat of other even worse variants emerging remains very real. (BA.2.75, an Omicron subvariant recently detected in India, is the newest one to rapidly attract scientists’ attention.)

BA.5 and BA.4 continue to outcompete the other Omicron subvariants across the U.S. and BA.5 is well on its way to becoming the dominant variant in the U.S. and around the world. As of the week ending June 25, the CDC’s NowCast model estimated that BA.4 and BA.5 together comprised a majority (over 52 percent) of U.S. cases for the first time. BA.2.12.1 is still the most prominent individual variant, making up an estimated 42 percent of cases, but that is down from an estimated peak of just over 63 percent of cases a month ago. The CDC estimates that BA.5 makes up 36.6 percent of cases — up 32 points from a month ago.