Vaccinia virus in Feces and Urine of Wild Rodents from São Paulo State, Brazil

Abstract

The origin of Vaccinia virus (VACV) outbreaks in Brazil remains unknown, but since the isolation of VACV in Mus musculus mice during a zoonotic outbreak affecting cattle and milkers, peridomestic rodents have been suggested to be a link between cows and wild animals. Considering that experimentally infected mice eliminate viral particles in their feces, we investigated the presence of VACV in the feces and urine of wild rodents that were captured in the forest areas surrounding milking farms in the central west region of São Paulo State. For the first time, this work reports the detection of VACV by PCR in the feces of naturally infected Oligoryzomys flavescens, Oligoryzomys nigripes, and Sooretamys angouya, and in the urine of Oligorizomys flavescens, which raises important questions about the spread of VACV by rodent feces and its potential to induce clinical infections in cows.

Keywords: PCR; Vaccinia virus; epidemiology; public health; transmission; wild animals.

Figure 1

Map of the sampling sites in Brazil (A) with São Paulo State shown in black. São Paulo state map (B) with Torre de Pedra, Bofete, and Anhembi in red. Map of São Paulo State (C) showing the sampling sites; the points in red correspond to the farms in Torre de Pedra (D); Bofete (E); and Anhembi (F). Source: Peres et al., 2013 [14].

Figure 2

Phylogenetic tree based on the OPV nucleotide sequence of the vgf gene showing the rodent strain (sample) cluster. In bold, the out group shope fibroma virus (SFV).

Figure 3

Alignment of the rodent strain (SAMPLE) sequences showing the polymorphism in red.