Dramatic FLU virus mutations may be due to antiquated vaccine manufacturing

Researchers discovered that by manufacturing the vaccine through the use of chicken eggs it had the unintentional consequence of causing dramatic mutations in the H3N2 Virus. These mutations the researchers speculate resulted in a equally dramatic decline in vaccine effectiveness

Prediction of influenza vaccine effectiveness for the influenza season 2017/18 in the US [version 1; referees: 1 approved]. F1000Research 2017, 6:2067 (doi: 10.12688/f1000research.13198.1)

A structural explanation for the low effectiveness of the seasonal influenza H3N2 vaccine  (doi: /10.1371/journal.ppat.1006682)