The US FDA’s Vaccines and Related Biological Products Advisory Committee has chosen the influenza vaccine strains for the 2018-2019 season in the Northern Hemisphere, which begins in the fall of 2018.

On February 22, the World Health Organization made its recommendations as to which influenza strains to include in vaccines for the coming influenza season. The committee voted on those recommendations today.

Overall vaccine effectiveness against influenza A(H3N2) — the predominant strain of influenza this season — has been 25% as of February 15.

FDA Commissioner Scott Gottlieb, MD, said in a February 26 news release that he believes the influenza A(H3N2) virus strain selected for this season’s vaccine was appropriate and that experts are working to determine why the vaccine was less effective than expected.