New so-called "FLiRT" COVID-19 variants have quickly become the most dominant in the United States, and authorities are monitoring their rise as summer approaches. According to the latest data from the Centers for Disease Control and Prevention (CDC), one of the two members of the “FLiRT” group, KP.2, is now No. 1 among strains nationally, accounting for about 24.9 of all current infections. The JN.1 strain had been dominant in the US before the emergence of KP.2. Both variants are offshoots of the highly contagious Omicron strain. The No. 4 variant in the US, KP.1.1, which makes up 7.5 percent...