Concerns for others increase the likelihood of vaccination against influenza and COVID-19 more in sparsely rather than densely populated areas

Significance Vaccination yields the prosocial benefits of preventing the spread of infectious diseases and protecting communities from major disease outbreaks. This research examines how focusing on prosocial concerns motivates vaccination across environments with varying levels of social density. Contrary to the common intuition that prosocial concern should motivate vaccination more in denser areas with more social contacts and disease transmission risk, our results show that prosocial concern yields higher vaccination rates in sparser areas where people believe that their behavior will have more impact. This research identifies emphasizing prosocial aspects of vaccination as one means by which public health interventions can reduce the rural−urban disparity in vaccination.