Volume 18, Number 1—January 2012
Vaccinia Virus Zoonotic Infection, São Paulo State, Brazil
To the Editor: Since 1999, vaccinia virus (VACV) has been isolated frequently from dairy cattle and humans (1–3). During bovine vaccinia outbreaks, VACV can be transmitted to farmers and those who milk cows; it frequently causes lesions on the hands and forearms. Bovine vaccinia causes economic losses and affects public health services in Brazil (1–4). One of the first VACV viruses isolated during Brazilian bovine vaccinia outbreaks was Araçatuba virus (ARAV), which was collected in São Paulo State, and since that time, other VACVs have been isolated in this state (2,5,6).
The circulation of VACV in São Paulo forests was described in the 1960s and 1970s, although such isolates seem to be phylogenetically distinct from ARAV and other VACVs that currently circulate in Brazil (7). Although VACV in several Brazilian states has been reported (1–3), the intrastate spread of VACV concerns veterinary and medical authorities and presents a challenge to the sanitary barriers and prophylactic measures implemented to date. We report 2 zoonotic bovine vaccinia outbreaks in the midwestern region of São Paulo State, Brazil.
The Institutional Ethics and Animal Welfare Commission from the Faculdade de Midicina Veterinária e Zootecnia–Universidade Estadual Paulista Júlio de Mesquita Filho/Campus de Botucatu approved this study. In 2009 and 2010, exanthematic outbreaks were reported in rural areas of Itatinga (23°6′7′′S, 48°36′57′′W) and Torre de Pedra (23°14′38′′S, 48°11′42′′W) counties, respectively. Between the 2 outbreaks, lesions were observed on the teats and udders of 10 lactating cows. The lesions appeared as macules, evolved into vesicles, pustules, and ulcers and healed after 2–3 weeks. Lesions developed on the hands and arms of the milkers after occupational contact with sick animals. The milkers also described headache, lymphadenopathy, and fever.
Specimens from 7 scabs and 1 vesicle were collected for virus identification by laboratory assays. After DNA extraction (InvitekDNA, Berlin, Germany), the samples were subjected to a specific orthopoxvirus PCR for the amplification of the A56R gene of vaccinia virus (8). A fragment of ≈950 bp was amplified from 5 exanthematic lesions. Two milk samples collected from sick cows were also positive for A56R. Parapoxvirus DNA was not detected in any collected sample (9). Material from the bovine and human exanthematic lesions induced characteristic poxvirus cytopathic effects in baby hamster kidney cells. In addition, 13 of the 18 collected bovine serum specimens were positive for orthopoxvirus according to a plaque reduction neutralization test and an ELISA (4). Human serum specimens were negative for orthopoxvirus by the plaque reduction neutralization test but positive by IgM ELISA, indicating the occurrence of an acute infection process (4).
A56R-PCR amplicons from 2 exanthematic lesions and 2 milk samples were sequenced in both orientations by using the Mega-BACE-sequencer (GE Healthcare, Little Chalfont, UK). Optimal alignment of our samples and other orthopoxvirus A56R gene sequences with ClustalW (www.ncbi.nlm.nih.gov/pmc/articles/PMC308517) by using MEGA3.1 (www.megasoftware.net) showed that a signature deletion was present in the sequences of several Brazilian VACV isolates (1–3). Three of the 4 sequenced amplicons exhibited 100% identity: the milk samples and a lesion collected from a same county. VACV samples from Itatinga and Torre de Pedra showed high identity with ARAV (2) and other Brazilian VACVs, including the Cantagalo (1) and Mariana viruses (10). A phylogenetic tree based on the A56R gene was constructed with the neighbor-joining method, 1,000 bootstrap replicates, and the Tamura 3-parameter model (MEGA3.1) (Figure). VACVs from Itatinga and Torre de Pedra clustered with several VACVs isolated during bovine vaccinia outbreaks. The A56R sequences obtained in this study were deposited in GenBank (accession no. It1446645).
We describe a new zoonotic outbreak of bovine vaccinia in São Paulo State, Brazil. Our molecular data suggest that this outbreak was caused by a VACV that is genetically related to viruses isolated in previous years, including ARAV, which was isolated in 1999 (2). The emergence and reemergence of this virus in previously bovine vaccinia–free microregions of São Paulo State suggest that VACV could have adapted to a specific microbiome and that the virus may be circulating not only in cattle and humans but also in some wild reservoir (10). Although genetic and ecologic studies of Brazilian VACVs have advanced in the past several years, little has been achieved in terms of bovine vaccinia prevention and control. Therefore, bovine vaccinia surveillance and public communication are critical in areas where VACV circulates.
- Damaso CR, Esposito JJ, Condit RC, Moussatche N. An emergent poxvirus from humans and cattle in Rio de Janeiro State: Cantagalo virus may derive from Brazilian smallpox vaccine. Virology. 2000;277:439–49.
- de Souza Trindade G, da Fonseca FG, Marques JT, Nogueira ML, Mendes LC, Borges AS, Araçatuba virus: a vaccinialike virus associated with infection in humans and cattle. Emerg Infect Dis. 2003;9:155–60.
- Medaglia MLG, Pessoa LCGD, Sales ERC, Freitas TRP, Damaso CR. Spread of Cantagalo virus to northern Brazil. Emerg Infect Dis. 2009;15:1142–3.
- Silva-Fernandes AT, Travassos CEPF, Ferreira JMS, Abrahão JS, Rocha ES, Viana-Ferreira F, Natural human infections with Vaccinia virus during bovine vaccinia outbreaks. J Clin Virol. 2009;44:308–13.
- Megid J, Appolinario CM, Langoni H, Pituco M, Okuda LH. Vaccinia virus in humans and cattle in southwest region of São Paulo state, Brazil. Am J Trop Med Hyg. 2008;79:647–51.
- Nagasse-Sugahara TK, Kisielius JJ, Ueda-Ito M, Curti SP, Figueiredo CA, Cruz AS, Human vaccinia-like virus outbreaks in São Paulo and Goiás States, Brazil: virus detection, isolation and identification. Rev Inst Med Trop Sao Paulo. 2004;46:315–22.
- de Souza Lopes O, Lacerda JP, Fonseca IE, Castro DP, Forattini OP, Rabello EX. Cotia virus: a new agent isolated from sentinel mice in São Paulo, Brazil. Am J Trop Med Hyg. 1965;14:156–7.
- Ropp SL, Jin Q, Knight JC, Massung RF, Esposito JJ. PCR strategy for identification and differentiation of smallpox and other orthopoxviruses. J Clin Microbiol. 1995;33:2069–76.
- Inoshima Y, Morooka A, Sentsui H. Detection and diagnosis of parapoxvirus by the polymerase chain reaction. J Virol Methods. 2000;84:201–8.
- Abrahão JS, Guedes MI, Trindade GS, Fonseca FG, Campos RK, Mota BF, One more piece in the VACV ecological puzzle: could peridomestic rodents be the link between wildlife and bovine vaccinia outbreaks in Brazil. PLoS ONE. 2009;4:e7428.
Suggested citation for this article: Megid J, Borges IA, Abrahão JS, Trindade GS, Appolinário CM, Ribeiro MG, et al. Vaccinia virus zoonotic infection, São Paulo State, Brazil [letter]. Emerg Infect Dis [serial on the Internet]. 2012 Jan [date cited]. http://dx.doi.org/10.3201/eid1801.110692
- Page created: December 15, 2011
- Page last updated: December 15, 2011
- Page last reviewed: December 15, 2011
- Centers for Disease Control and Prevention,
National Center for Emerging and Zoonotic Infectious Diseases (NCEZID)
Office of the Director (OD)