As of May 11, COVID-19 variant KP.2 has become the dominant strain in the U.S., accounting for more than 28% of cases nationwide, per CDC data.
KP.2 is part of what has been dubbed the "FLiRT" variants, which references COVID-19 strains that have been named to the group because of technical names for the variants' mutations in their spike proteins, according to the American Medical Association.
"KP.2 is the main variant in the U.S., but isn’t causing an increase in COVID-19 infections or more severe illness than other variants," the CDC stated in a post on X, formerly Twitter, May 15.
While KP.2 may not be more severe than previous variants, it, along with other the FLiRT variants like JN.1 could drive a possible surge in summer COVID-19 infections, according to Andy Pekosz, PhD, a professor of molecular microbiology and immunology at Johns Hopkins Bloomberg School of Public Health in Baltimore.
"The FLiRT variants would be high on my list of viruses that could cause another wave of infections in the U.S.," Dr. Pekosz said during a Q&A with the school. "That said, our definition of a wave has changed; while we still see case rates rise and fall throughout the year, we see much lower numbers of cases of hospitalizations or deaths than we saw in the first couple years of the pandemic. And yet, while these waves are becoming smaller, they are still having the greatest impact on our susceptible populations…"
Here are three other notes on the new FLiRT variants:
- The COVID-19 vaccine that rolled out in fall 2023 may still offer protection against some of these variants, according to Johns Hopkins experts.
- The FDA's meeting regarding fall 2024 COVID-19 vaccine updates was postponed from May 16 until June 5. At this meeting, they will discuss updates to the next iteration of the vaccine, likely in line with what the World Health Organization recommended in April – to base them off the JN.1 variant.
- Individuals who have recently had a COVID-19 infection, if the lineage was JN.1 or KP.2 are likely to have strong immunity protection from those strains in the meantime.