The FLiRT COVID-19 variants, including KP.2 and KP.1.1, have emerged in the United States and now account for over 25% of cases nationwide. These new variants are raising concerns due to their potential for increased transmissibility and ability to evade prior immunity, sparking worries of a possible summer wave of infections. Despite a decrease in cases and hospitalizations, the virus continues to mutate, leading to the emergence of new strains.
KP.2 and KP.1.1 are spinoffs of the omicron subvariant JN.1.11.1 and have additional mutations that give them a competitive edge over other variants. KP.2 has quickly become the dominant strain in the U.S., making up a significant portion of current cases. The name “FLiRT” was coined on social media to simplify the technical names of these variants, which often comprise a combination of letters and numbers. The name FLiRT is derived from the mutations at positions 456 (F for L) and 346 (R for T) in the spike protein.
The naming of variants is based on a Pango lineage classification system, where each variant has a unique combination of letters and numbers. The FLiRT variants are considered sublineages of the omicron branch, BA.2.86 or Pirola. The continued mutations and changes in the virus create lengthy and complex technical names, making nicknames such as FLiRT more accessible and easier to remember. The World Health Organization has also introduced a simplified system for naming key variants using letters of the Greek alphabet.
Despite the playful name, the FLiRT variants and other COVID-19 strains are a serious public health concern. It is essential for individuals to stay vigilant, follow precautions, and continue to receive vaccinations to prevent severe disease and complications. Remaining informed about the latest developments in the pandemic and understanding the nature of new variants can help individuals make informed decisions to protect themselves and others from COVID-19.
