Reviewed by Dr. Eddie Hackler III
Wheelock A, et al. BMJ Open. 2017 Jul 12;7(7):e014668. doi: 10.1136/bmjopen-2016-014668

This study is a cross-sectional survey designed to identify policy-amenable factors related to influenza vaccination rates in 3 high-income countries. Adults from the USA, UK, and France were randomly surveyed regarding influenza vaccination between March and April 2014 via online surveys and telephone interviews. Quotas based on gender, age, income, region, ethnicity and settlement type (rural/urban) were used to ensure national representativeness. The online survey was completed by 814 participants in the USA, 791 in the UK, and 787 in France. Via telephone, 80 participants were interviewed in the USA, and 100 in each the UK and France (total N=2412). Data were analyzed using multivariable logistic regression. Generally, the responses of vaccinated and unvaccinated individuals were significantly different. Vaccinated participants were older, insured, wealthier (USA/France), more educated (USA), more concerned about the risks of influenza than the risks of the vaccine and reported a better understanding of the influenza vaccine than unvaccinated individuals. The regression models were able to explain 64-80% of the variation in vaccination rates. Sociopsychological variables (influenza and vaccine risk perceptions, vaccine effectiveness, self-efficacy, perceived knowledge of the vaccine, and trust in key vaccination stakeholders) accounted for more of the variance in past influenza vaccination behavior than demographic, socioeconomic, and health variables (49% vs 22% in the USA, 42% vs 38% in the UK and 45% vs 19% in France).

Approximately 49,000 people die every year in the United States from influenza-related illness, but vaccination rates among high risk patients remain sub-optimal. In 2013-2014, only 65% of adults over age 65 and 46% of younger adults at high risk for influenza-related complications were vaccinated in the USA. Vaccination decisions are influenced by numerous factors, including demographic, socioeconomic and sociopsychological factors, with the latter being amenable to policy interventions.

This study suggests that sociopsychological factors heavily influence vaccination behaviors, with the most policy-amenable factors being social influence and perceptions about influenza. These factors are not consistently assessed but could be used to monitor vaccination sentiment and predict uptake in the population through national immunization surveys. The influence of physician opinion on vaccination rates suggests that improving patient and provider communication should be prioritized. Incentives for providers have been suggested. Efforts should also focus on closing the gap between perceived and actual risks of influenza, with tailored messaging regarding risks to specific groups.

In our PRIME and PCIM clinics, we have a number of individuals who decline the annual influenza vaccine. This study suggests that social influence, specifically from physicians, can increase compliance with vaccination. We have an opportunity each flu season to directly encourage our patients to be vaccinated and to place emphasis on the risks of influenza in specific age and chronic illness groups, which allows us to be a part of lowering the morbidity and mortality from influenza in the United States.