Adjuvanted Flu Shots Prevent Hospitalizations and Reduce Associated Costs

Researchers recently wrote in an original research article that getting an annual flu shot is highly recommended. Still, influenza vaccines do not work as well in older adults due to the aging of their immune systems.

One approach to improving influenza vaccine efficacy is the addition of an adjuvant to the vaccine to boost an individual's immune response.

Published on December 19, 2023, this new study evaluated an adjuvanted vaccine compared to an unadjuvanted vaccine for preventing cardiorespiratory hospitalizations and hospitalization costs.

The Original Research's findings demonstrated that the adjuvanted flu vaccine, compared to the unadjuvanted vaccine, prevented more hospitalizations and significantly reduced associated hospital costs.

The study included 715,807 aIIV3 and 320,991 IIV4e recipients in the 2018–19 and 844,169 aIIV3 and 306,270 IIV4e recipients in the 2019–20 influenza seasons.

aIIV3 vaccination was significantly more effective than IIV4e in preventing cardiorespiratory disease (2018–19 rVE = 6.2%; and 2019–20 rVE = 6.0%) and respiratory disease (2018–19 rVE = 8.9%; and 2019–20 rVE = 10.1%).

During the 2018–19 flu season, cardiorespiratory hospitalization cost savings for the aIIV3 population were $392 million and $ 221 million for the 2019–20 season.

Respiratory hospitalization cost savings for the aIIV3 population were $145 million and $97 million, respectively.

As of December 20, 2023, over 153 million influenza vaccines (nasal, egg-based, cell-based) were distributed this flu season in the U.S. These vaccines are generally available at clinics and local pharmacies.