An Update on the Known Host Range of the Brazilian Vaccinia Virus: An Outbreak in Buffalo Calves

Abstract

Even nearly forty years after the eradication of smallpox, members of the Poxviridae family continue to be the focus of an increasing number of studies. Among these studies, prominently stands vaccinia virus, an orthopoxvirus that is associated with bovine vaccinia outbreaks. Although more frequently associated with infections in cattle and humans, the host range of vaccinia virus is not restricted only to these hosts. There are several instances of molecular and serological evidence of circulation of vaccinia virus among wildlife species. In addition, viral isolation has confirmed a broad spectrum of vaccinia virus hosts. In this report, we provide a brief update on the host range of Brazilian vaccinia virus, and present a case description of an outbreak in domestic buffalo calves from Northeastern Brazil that corroborates previous serological and molecular studies. Furthermore, in the present study, vaccinia virus has been isolated for the first time in buffaloes, and referred to as vaccinia virus Pernambuco (VACV-PE). Phylogenetic reconstruction was based on A56R clustered VACV-PE with vaccinia virus isolates belonging to group 1 Brazilian vaccinia virus. Furthermore, the vaccinia virus genome was detected in the milk of a lactating cow, which thereby revealed a pathway for future studies on the possible impact of vaccinia virus on buffalo milk and milk products. Taken together, these results provide the first description of clinical disease caused by vaccinia virus in buffaloes in South America. They also raise new questions about the chain of transmission of this virus.

Exposure of free‐ranging capybaras ( Hydrochoerus hydrochaeris ) to the vaccinia virus

“…Recently, the dynamics of VACV circulation has been updated (Lima et al, ) and it has been suggested that capybaras are a common link between urban, wild and rural areas while spreading the virus. This function of being a common link (Lima et al, ) fortifies the hypothesis that capybaras might be VACV reservoirs or a source of infection.…”

“…Recently, the dynamics of VACV circulation has been updated (Lima et al, ) and it has been suggested that capybaras are a common link between urban, wild and rural areas while spreading the virus. This function of being a common link (Lima et al, ) fortifies the hypothesis that capybaras might be VACV reservoirs or a source of infection. This renders our results relevant as these asymptomatic carriers were collected on roads (near or within the city) and without any link to BV outbreaks, suggesting that the capybaras had been exposed to the OPV in the wild.…”

Circulation of Vaccinia virus in Southern and Southeastern wildlife, Brazil

“…BV has been predominantly reported in rural areas, affecting mainly dairy cattle and humans, being a burden to public health and local dairy economies (Oliveira et al, 2017). Additionally, VACV has also been detected in other species present in the rural environment (equids and buffaloes) (Lima et al, 2019) and domestic animals in urban areas (dogs and cats) (Costa et al, 2018; Oliveira et al, 2017). However, VACV natural history and circulation in wildlife are still poorly explored (Miranda et al, 2017; Oliveira et al, 2017).…”

“…Few studies have documented the circulation of VACV in synanthropic and wild rodents (Abrahão et al, 2009; Miranda et al, 2017), and also in other sylvatic animals such as primates, marsupials and coatis (Abrahão et al, 2009; Costa et al, 2018; Lima et al, 2019; Miranda et al, 2017; Oliveira et al, 2017). Aiming to include the wildlife in the VACV transmission cycle, ecological models have been proposed (Costa et al, 2017, 2018; Lima et al, 2019; Oliveira et al, 2017). According to the models, sylvatic animals could potentially act in VACV transmission between rural, wild and even urban environments (Abrahão et al, 2009; Costa et al, 2018; Lima et al, 2019; Oliveira et al, 2017).…”

“…Aiming to include the wildlife in the VACV transmission cycle, ecological models have been proposed (Costa et al, 2017, 2018; Lima et al, 2019; Oliveira et al, 2017). According to the models, sylvatic animals could potentially act in VACV transmission between rural, wild and even urban environments (Abrahão et al, 2009; Costa et al, 2018; Lima et al, 2019; Oliveira et al, 2017). Furthermore, VACV could also circulate silently in areas with very few cattle herd and anthropogenic disturbance (Kurth et al, 2008).…”