H3N2 mutation in last year's flu vaccine responsible for lowered efficacy

(University of Pennsylvania School of Medicine) The below average efficacy of last year's influenza vaccine (which was only 20 to 30 percent effective) can be attributed to a mutation in the H3N2 strain, a new study reports. With the mutation, most people receiving the egg-grown vaccine did not have immunity against H3N2 viruses that circulated last year.

https://www.eurekalert.org/pub_releases/2017-11/uops-hmi110317.php

Source: EurekAlert! - Infectious and Emerging Diseases - November 6, 2017 Category: Infectious Diseases Source Type: news