Despite the current low Covid cases in the U.S., experts are already focusing on strategies to prevent a potential surge in the upcoming winter season. The emergence of the highly contagious JN.1 variant in late August, followed by offshoots like the FLiRT variants, KP.1.1, and KP.2, has prompted vaccine experts to consider updating the vaccines to effectively combat these evolving strains.

Natalie Thornburg, a research microbiologist at the CDC, highlighted a pattern where a dominant "parent" strain of the virus establishes itself in early winter, giving rise to various descendants by spring, as observed with strains like XBB from the past year. The FDA advisory panel's unanimous recommendation emphasized the importance of targeting the JN.1 strain or its descendants for the updated vaccines, with a preference expressed by most members towards focusing on JN.1 due to its prevalence.

The FDA's top vaccine regulator, Dr. Peter Marks, stressed the need to consider the more recent strains like KP.2 for the updated vaccines, emphasizing the benefits of mRNA-based vaccines for their speed in development and production. Pfizer, Moderna, and Novavax have plans to roll out updated vaccines targeting JN.1 or the selected strain in time for the fall vaccination campaign, with data showing increased antibody levels against circulating virus strains with the new vaccines. Additionally, with Covid hospitalizations at their lowest levels but signs of cases potentially increasing, the CDC is closely monitoring data to make informed vaccination recommendations for the upcoming season.