Targeted Vaccination

 

Policy-makers have been debating how to respond to an intentional release of smallpox in the United States. Halloran et al. (p. 1428; see the Perspective by Koopman) generated model communities of 2000 people, interacting within schools and neighborhoods. They looked at the effects of targeted vaccination of those in close contact with smallpox cases relative to mass vaccination carried out before or after the release event. The presence of residual immunity from prior vaccination increased the effectiveness of the targeted strategy more than mass vaccination. Under all strategies, targeted vaccination prevented more cases per dose of vaccine than did mass vaccination.