According to research conducted by Dr. Geoffrey Gorse of Saint Louis University, adding an additional strain of Influenza B could improve the effectiveness of the influenza vaccine. For reference, the current flu vaccine contains 2 strains of Influenza A viruses and 1 strain of Influenza B virus, totaling to offer protection against 3 influenza strains. Flu vaccines can either be trivalent or quadrivalent.
This study was conducted among 3,355 volunteer patients between the ages of 18 and 64 who opted to receive flu vaccines at 38 different vaccination sites in the United States. They were randomly selected to receive either the trivalent or quadrivalent vaccines. Follow-up data demonstrates that patients who received the quadrivalent vaccine had a superior antibody response as compared to those who received the trivalent vaccine. Additionally, results showed that adding an additional strain did not impact the ability of individuals to mount an immune response to other viral strains.
Perhaps in the future vaccine developers and the CDC (or other individuals in control of vaccination) will opt to include another influenza strain in the vaccine in order to protect against a wider range of viral strains. This might be especially prudent, especially given that 50% of the time in the past decade, the wrong lineage of influenza B strains have been chosen for the trivalent vaccine and in cases like this year wherein the vaccine has been dubbed as inappropriately targeted towards the circulating strains.