ABSTRACT
Vaccinia virus (VACV) has been associated with several exanthematic outbreaks in bovine, human, and equine species in Brazilian rural areas. Little is known about VACV reservoirs, although it is believed that rodents could be associated with VACV outbreaks. With the goal of filling one more gap in the VACV ecological puzzle, the present work aimed at mimicking a potential transmission route of VACV between cows and rodents, both known as natural VACV hosts. Balb/c mice were exposed to feces of experimentally VACV infected cows for 20 days, and samples from these mice were examined by using molecular and serological tests. VACV DNA was detected in feces and blood samples after several days of exposure; infectious VACV particles were also detected in the feces. The presence of anti-VACV neutralizing antibodies in murine sera further suggested horizontal transmission. If the transmission model described here can be applied to natural environments, exposure to bovine feces could be considered a risk factor for the spread of VACV; consequently, the traditional use of bovine manure as a fertilizer in agricultural activities may be promoting the infection of rodents.
