Animal infections by vaccinia-like viruses in the state of Rio de Janeiro: an expanding disease

Abstract

In the present study we investigated the presence of infections by vaccinia-like viruses in dairy cattle from 12 counties in the state of Rio de Janeiro in the last 9 years. Clinical specimens were collected from adult animals with vesicular/pustular lesions mainly in the udder and teats, and from calves with lesions around the nose and mouth. A plaque reduction neutralization test (PRNT) was applied to search for antibodies to Orthopoxvirus; the vesicular/pustular fluids and scabs were examined by PCR, electron microscopy (EM) and by inoculation in VERO cells for virus isolation. Antibodies to Orthopoxvirus were detected in most cases. The PCR test indicated a high nucleotide homology among the isolates and the vaccinia viruses (VACV) used as controls. By EM, typical orthopoxvirus particles were observed in some specimens. The agents isolated in tissue culture were confirmed as vaccinia-like viruses by EM and PCR. The HA gene of the vaccinia-like Cantagalo/IOC virus isolated in our laboratory was sequenced and compared with other vaccinia-like isolates, showing high homology with the original Cantagalo strain, both strains isolated in 1999 from dairy cattle. Antibodies to Orthopoxvirus were detected in one wild rodent (genus Akodon sp.) collected in the northwestern region of the state, indicating the circulation of poxvirus in this area. Nonetheless, PCR applied to tissue samples collected from the wild rodents were negative. Vesicular/pustular lesions in people in close contact with animals have been also recorded. Thus, the vaccinia-like virus infections in cattle and humans in the state seem to be an expanding condition, resulting in economic losses to dairy herds and leading to transient incapacitating human disease. Therefore, a possible immunization of the dairy cattle in the state should be carefully evaluated.

Outbreaks of vesicular disease caused by Vaccinia virus in dairy cattle from Goiás State, Brazil (2010-2012)

“…Probably, in the outbreaks 1-3, the proximity between the farms and the fact of the daily collection of produced milk in the three properties by the same truck could have favored the dissemination of the infection. Gross lesions noted in the cows and calves of the present study were similar to the ones described in other reports of VACV disease observed in Brazil (Trindade et al 2003, Schatzmayr et al 2009a). More severe lesions affecting also the perineal region and the inner thigh were described in other investigations (Reviewed by Lemos & Riet-Correa 2007).…”

“…Similar clinical symptoms were observed in humans beings in outbreaks described in other Brazilian states (Nagasse--Sugahara et al 2004, Megid et al 2008, Silva et al 2008, Schatzmayr et al 2009b). Sudoresis, anorexia, toxemia and lymph node swelling were also observed in some human cases (Silva et al 2008, Schatzmayr et al 2009a, 2009b. In comparison with other zoonotic vesicular disease, VACV infection appears to affect more severely and systematically the humans that have contact with the affected cattle (Büttner & Rziha 2002, Silva-Fernandes et al 2009).…”

Antibodies Anti-Orthopoxvirus in Healthy Workers Who Handle Animals and in Patients With Cutaneous Lesions Compatible With Poxvirus Infection in the State of Rio De Janeiro, Brazil

“…It is likely that the vaccine strains have been introduced into nature more than once. Over the years, several authors have confirmed the presence of infections in animals and humans by poxvirus, particularly in the Brazilian southeast (Mello et al 1960, Schatzmayr et al 2009a, 2009b, 2011Silva & Moraes 1962, Trindade et al 2003, Donatele et al 2007). It must be remembered that the smallpox vaccination campaign was discontinued in the country in the 1970s, which confirms that the vaccinialike virus is circulating in the country, a fact accepted in the international literature (Regnery 2007).…”

“…Damaso et al (2000) have shown that the virus, called Cantagalo (CTGV), isolated in municipalities with animals exhibiting vesicular/pustular disease is an Orthopoxvirus and that at the molecular level, this virus is very close to the sample vaccinia virus used in the past to prepare vaccines at the Instituto Oswaldo Cruz. Later, other authors confi rmed the circulation of similar viruses as a cause of infection in animals and humans, especially in the state of Rio de Janeiro and throughout southeastern Brazil (Costa et al 2007, Donatele et al 2007, Leite et al 2005, Nagasse-Sugahara et al 2004, Schatzmayr et al 2009a, Schatzmayr et al 2009b, Schatzmayr et al 2011, Trindade et al 2003, Trindade et al 2006, Trindade et al 2007. Th e movement of vaccinia virus has been confi rmed in the Brazilian territory and by reports in the international literature (Regnery 2007).…”

Estudo Epidemiológico do Vaccinia Virus na Região Sudeste do Brasil: Revisão de Literatura

“…O genoma desses vírus é constituído por DNA e potencialmente pode codificar cerca de 200 proteínas com diferentes funções, dentre elas, a replicação do DNA viral, a transcrição, a morfogênese da partícula, a interação aos hospedeiros e a evasão do sistema imune (MOSS, 2001;BULLER-PALUMBO, 1991). O Vaccinia vírus, foi utilizado como vacina para a campanha mundial de erradicação da varíola, devido à semelhança genética e antigênica entre o vírus causador da varíola o Orthopoxvirus variolae (SCHATZMAYR et al ., 2009) No Brasil, as campanhas de vacinação foram realizadas nas zonas rurais por equipes que se deslocavam de uma propriedade à outra, manipulando os frascos contendo a vacina viva com o vírus Vaccinia em altos títulos, sendo comum a não eliminação adequada dos materiais residuais, contendo restos do imunizante. Admite-se que estes procedimentos permitiram a implantação de amostras do Vaccinia vírus em ciclos naturais, pela infecção de animais reservatórios, como roedores silvestres, vindo a atingir posteriormente bovinos e pessoas que manejam estes animais.…”