Herd immunity Each vaccination protects not only the vaccine- recipient but also neighbors as well Even unvaccinated people benefit when their neighbors,friends,coworkers,and family become immune through vaccination Known as herd immunity Herd immunity is a classic positive externality: the social gain from each vaccinationis greater than the private gain from that vaccination. Bhattacharya,Hyde and Tu-HealthEconomics Bhattacharya, Hyde and Tu – Health Economics Herd immunity  Each vaccination protects not only the vaccine￾recipient but also neighbors as well  Even unvaccinated people benefit when their neighbors, friends, coworkers, and family become immune through vaccination  Known as herd immunity  Herd immunity is a classic positive externality: the social gain from each vaccination is greater than the private gain from that vaccination