Historical Virulence

An integrated analysis of the multiple factors involved in smallpox biodefense planning indicates that pre-attack voluntary, controlled smallpox vaccination would provide the most viable defense. The essential factors include the historical virulence and infectivity of smallpox, the contemporary lack of herd immunity, current response capabilities, vaccine risk, the likelihood and progression of a smallpox bioterror attack, the potential for global spread, psychosocial factors, and political factors