New FLiRT COVID Variant KP.2 Becomes Dominant

With the COVID-19 virus continuing to evolve, a new variant dubbed KP.2 has rapidly become the leading cause of COVID infection in the country, making up about 25 percent of new cases.

Latest data from the Centers for Disease Control and Prevention (CDC) show that the KP.2 strain has emerged from just 4 percent of cases a month ago. It has jumped past the formerly dominant JN.1 variant, which now makes up just 22 percent of new cases.

KP.2 is a member of a group of variants called FliRT (which is short for the technical names of their mutations). Recent CDC reporting shows that another FliRT variant, KP.1.1, has also been gaining steam and currently accounts for 7.5 percent of infections.

A Small Wave of Infection May Be Ahead

A preprint study in Japan published on BioRxiv indicated that KP.2 (which is a descendant of the omicron JN.1 strain) has an advantage over JN.1 because of three changes in its spike protein, which allow the virus to bind to cells and cause infection.

The Japanese researchers concluded that because of its higher viral fitness, KP.2 will potentially become the predominant lineage worldwide.

As we head into summer, Eric Topol, MD, the founder and director of the Scripps Research Translational Institute, predicted on his Substack blog that we could see “a wavelet but not a significant new wave of infections as a result of the FLiRT variants in “the next couple of months.”

Many Are Protected Against Serious Illness

While KP.2 may lead to a rise in new COVID cases, most people should have protection against severe illness and hospitalization because of antibodies from previous infection or vaccination, according to Edward Jones-Lopez, MD, an infectious disease specialist with Keck Medicine of USC in Los Angeles.