Measuring the Total Benefits of Influenza Vaccination

The total benefit to society from a single additional influenza vaccination includes the direct benefits to the individual receiving the vaccine and the indirect benefits to others. The indirect benefits of an influenza vaccine result from the fact that each vaccine reduces the spread of influenza throughout the population. Unfortunately, the total benefit of influenza vaccination is difficult to measure using standard methods of evaluating medical interventions (e.g., randomized controlled trials) since the total benefit can only be measured in an analysis at the population level. In a new study published in the Journal of Human Resources, Corey White estimates the total benefits of influenza vaccination in two different settings.

In the first setting, White uses a natural experiment to estimate the effect of state-level influenza vaccination rates on state-level mortality rates and work absences. Because the analysis is at the state level, it captures both the direct benefits of vaccination and the indirect benefits that occur within the state. The estimates imply that approximately 4,065 influenza vaccinations are required to save one life, and 1.92 vaccinations are required to save one 8-hour work day. Furthermore, White finds that nearly all of the mortality reductions operate through the indirect effects of influenza vaccination.

In the second setting, White examines a group for whom the potential indirect benefit of vaccination is particularly large: healthcare workers. By analyzing the effects of county-level laws in California that require influenza vaccination for healthcare workers, White finds that the total benefit of each vaccination is approximately 10 times greater for healthcare workers compared to the general population.

The results of this study indicate that policies increasing take-up of influenza vaccination in either the general population or in the population of healthcare workers not only save lives but are likely to be cost-effective.

Read the full study in the Journal of Human Resources: “Measuring the Social and Externality Benefits of Influenza Vaccination,” by Corey White.

Corey White (@corey_d_white) is currently at Cal Poly, San Luis Obispo (through August 2020) and IZA.