“It is unlikely that B/Yamagata-lineage viruses are circulating in the population. Therefore, it is the opinion of the WHO influenza vaccine composition advisory committee that the inclusion of B/Yamagata-lineage antigens in influenza vaccines is no longer warranted,” the agency said when it released its recommendations for 2024 flu vaccines Sept. 29.
Instead, the WHO is recommending a trivalent vaccine for the 2024 Southern Hemisphere flu season that should target two influenza A viruses — H1N1 and H3N2 — and an influenza B/Victoria virus.
Vaccines for the current flu season in the U.S. still include a Yamagata lineage virus.
