Group 1 Vaccinia virus zoonotic outbreak in Maranhao State, Brazil.

In Brazil, several exanthematic autochthone Vaccinia virus (VACV) outbreaks affecting dairy cattle and rural workers have been reported since 1999. Although outbreaks had been first described in the Brazilian Southeast, VACV outbreaks were notified in all Brazilian regions in < 10 years. However, in this context, VACV outbreaks had not been described in some Brazilian States, likely because of a lack of notification, or yet unknown epidemiological reasons. Here, we describe the first VACV outbreak in Maranhão State, northeastern Brazil. The virus isolated from this outbreak showed several biological and molecular features that resemble other Group 1 Brazilian VACV, including a deletion signature in the A56R gene. This study raises new questions about diversity and epidemiology of Brazilian VACV.