FDA's ongoing efforts to help improve effectiveness of influenza vaccines

FDA Commissioner Scott Gottlieb, MD, said Monday the agency is investigating reduced effectiveness of 2017–18 seasonal influenza vaccines against the H3N2 strain of influenza A. "There are a number of theories on why this season's vaccines produced reduced effectiveness against H3N2," Gottlieb said.

FDA Commissioner Scott Gottlieb, MD, said Monday the agency is investigating reduced effectiveness of 2017–18 seasonal influenza vaccines against the H3N2 strain of influenza A. "There are a number of theories on why this season's vaccines produced reduced effectiveness against H3N2," Gottlieb said. "We're taking steps to investigate each of these potential causes, rule out possible reasons for the variation in effectiveness, and improve vaccine efficacy against H3N2." According to CDC, preliminary vaccine effectiveness for H3N2 influenza was 25%. "While that finding isn't too far off from the vaccine effectiveness seen against H3N2 in previous years, we need to take new steps to improve vaccine efficacy against H3N2," Gottlieb asserted, noting a wide disparity in vaccine effectiveness against H3N2 among young children and older adults. FDA researchers are working with CMS to use a large database that includes details of the influenza vaccines administered to 4 million people along with whether they were hospitalized for influenza or treated with antiviral medications for influenza-like illness. This work, Gottlieb said, will try to determine why the overall effectiveness with both the cell-based and egg-based vaccines was less than optimal. The composition of next season's influenza vaccines will be discussed by an FDA advisory committee on March 1. Gottlieb explained, "As is done every year, the FDA convenes this panel to consider the recommendations made by the World Health Organization regarding the composition of influenza vaccines for the Northern Hemisphere, and to help the FDA select strains for next season's flu vaccines in the U.S." He noted that although there has been a decline in influenza-related visits to doctor's offices and outpatient clinics, the current season is not yet over. Gottlieb stressed the important of good hand hygiene and said it is not too late to get vaccinated, if you have not done so.