Group 2 Vaccinia Virus, Brazil

Felipe Lopes Assis, Iara Apolinario Borges, Paulo César Peregrino Ferreira, Cláudio Antônio Bonjardim, Giliane de Souza Trindade, Zélia Inês Portela Lobato, Maria Isabel Maldonado Guedes, Vaz Mesquita, Erna Geessien Kroon, and Jônatas Santos Abrahão

Author affiliations: Author affiliation: Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil

Abstract

In 2011, vaccinia virus caused an outbreak of bovine vaccinia, affecting dairy cattle and dairy workers in Brazil. Genetic and phenotypic analyses identified this isolate as distinct from others recently identified, thereby reinforcing the hypothesis that different vaccinia virus strains co-circulate in Brazil.

Throughout most of Brazil, vaccinia virus (VACV), family Poxviridae, is the etiologic agent of bovine vaccinia (1). Outbreaks often occur on unhygienic rural properties and cause mild to severe rashes on teats and udders of dairy cows and various locations on humans (1,2). Dairy workers usually seek medical care for the painful lesions, but rarely are they hospitalized. Some studies suggest an association between these outbreaks of bovine vaccinia and the VACV strains used during the World Health Organization smallpox eradication campaign (3). Since 1999, VACV strains in Brazil have been investigated (2–8); biological and molecular approaches indicated 2 distinct groups of these viruses (9,10). In 2011, a bovine vaccinia outbreak occurred in Serro County, Minas Gerais state, in southeastern Brazil, one of the largest milk-producing regions in Brazil. The outbreak affected 91 dairy cows and 3 dairy workers, 1 of whom was hospitalized (Technical Appendix Figure 1