Vaccines at work: experimental evidence from a firm campaign

Health campaigns in firms could be a cost-effective approach to reduce sickness absence and to mitigate negative economic consequences of ill-health among employees. Low participation rates, however, may prevent firms from realizing such private economic benefits. Moreover, employees may overestimate the effects of the campaign and engage in risky behaviors that could be detrimental to their health, thereby reducing the potential benefits of the intervention. We ran a natural field experiment with a bank in Ecuador, where we employed a randomized encouragement design by experimentally manipulating incentives to participate in a campaign to get vaccinated against influenza. This allows us to study the determinants of on-site vaccination and the consequences of increased participation in a firm campaign for employees, thereby informing about the private incentives for firms to run such interventions. Using rich administrative records merged with employee survey data, we find strong evidence that opportunity costs to participate in the campaign and peer behavior in the firm matter to increase vaccination take-up. Contrary to the firm’s expectation, increased participation in the campaign did not imply reduced sickness absence during the flu season. As we observe no relevant health benefits or externalities via co-worker vaccination, our comprehensive analyses indicate that the campaign most likely was not economically beneficial for the firm. We discuss potential explanations for this result and present evidence consistent with the notion that a vaccination campaign can influence the behavior of employees concerning their health.