Vaccinia Virus in Blood Samples of Humans, Domestic and Wild Mammals in Brazil.

Marina Peres,Fernando Ferreira,Bruna Ribeiro,Jonatas Abrahão,Camila Appolinário,Jane Megid,Acácia Vicente,Mateus Mioni,Vanessa Pelícia,Graziele Oliveira,Thais Bacchiega,Clóvis Fonseca

doi:10.3390/v10010042

Abstract

Outbreaks of Vaccinia virus (VACV) affecting cattle and humans have been reported in Brazil in the last 15 years, but the origin of outbreaks remains unknown. Although VACV DNA have been already detected in mice (Mus musculus), opossums (Didelphis albiventris) and dogs during VACV zoonotic outbreaks, no transmission to cattle or humans from any of these were reported during Brazilian outbreaks. In this work, we assessed the PCR positivity to VACV in blood samples of cows and other domestic mammals, wild rodents and other wild mammals, and humans from areas with or without VACV infection reports. Our results show the detection of VACV DNA in blood samples of cows, horse and opossums, raising important questions about VACV spread.

Highlights

The first official report of a Vaccinia virus (VACV) outbreak in cattle and humans in Brazil was recorded in 1999 at Cantagalo city, Rio de Janeiro State [1]
The positive animals were from Anhembi (0.7%) and Bofete (0.7%), and no positivity were detected in blood samples from Torre de Pedra (Table 2), where VACV zoonotic outbreaks were previously reported [3,6]
We assessed the presence of VACV in bovine herds and in other domestic and wild mammals, as well as in humans from milk farms located in areas with and without official reports of zoonotic outbreaks

Summary

Introduction

The first official report of a Vaccinia virus (VACV) outbreak in cattle and humans in Brazil was recorded in 1999 at Cantagalo city, Rio de Janeiro State [1]. It was believed that VACV reemergence in zoonotic outbreaks was related to the VACV vaccines strain used during campaigns of World Health Organization (WHO). It is known that VACV isolated in Brazilian outbreaks is divergent from VACV vaccines strains, but the origin of outbreaks remains unknown [11,12]. In this way, a model of transmission has been proposed in which peridomestic rodents act as a link between domestic animals and wildlife [13]. Peridomestic rodents like Mus musculus, Rattus rattus and Rattus norvergicus act as host reservoirs of cowpox virus in Europe [14]. The members of Rodentia order have been targeted of research looking for explaining its possible role in the VACV spread [15,16,17,18]

Methods

Results

Conclusion