Why experts anticipate new COVID-19 shots to be effective, despite flurry of strains 

New COVID-19 shots targeting omicron subvariant XBB.1.5 are slated to be ready in September. That strain only accounts for about 10 percent of U.S. cases, though experts say other circulating strains are similar enough to XBB.1.5 that the new shots should still be effective.