Clin Infect Dis
Clin Infect Dis. serosurvey Thirty-four years ago, the world celebrated the eradication of smallpox, a lethal disease caused by Variola virus infection. The massive antismallpox vaccination campaign was promoted by the World Health Organization (WHO) during the 1960s and 1970s (Fenner et al. 1988, Damon 2013). Vaccinia virus (VACV), a species belonging to the Orthopoxvirus…