RESUMO
To investigate an outbreak of avian pox in psittacines in a conservation facility, we examined 94 birds of 10 psittacine species, including sick and healthy birds. We found psittacine pox virus in 23 of 27 sick birds and 4 of 67 healthy birds. Further characterization is needed for these isolates.
Assuntos
Avipoxvirus/genética , Doenças das Aves/epidemiologia , DNA Viral/genética , Surtos de Doenças , Infecções por Poxviridae/veterinária , Psittaciformes/virologia , Animais , Avipoxvirus/classificação , Avipoxvirus/isolamento & purificação , Avipoxvirus/patogenicidade , Bioensaio , Doenças das Aves/mortalidade , Doenças das Aves/virologia , Brasil/epidemiologia , Embrião de Galinha , Membrana Corioalantoide/patologia , Membrana Corioalantoide/virologia , Conservação dos Recursos Naturais , Fezes/virologia , Filogenia , Reação em Cadeia da Polimerase , Infecções por Poxviridae/epidemiologia , Infecções por Poxviridae/mortalidade , Infecções por Poxviridae/virologia , Pele/patologia , Pele/virologiaRESUMO
Vaccinia virus (VACV) has been associated with several bovine vaccinia outbreaks in Brazil, affecting cattle and humans. There are no available data about VACV environmental circulation or the role of wildlife in the emergence of an outbreak. Since VACV was isolated from rodents in Brazil, we investigated shedding and transmission of VACV strains in mice. The VACV excretion profile was assessed by PCR and chicken chorioallantoic membrane infection, revealing viral DNA and infectious virus in the faeces and urine of intranasally infected mice. Horizontal transmission was assessed by exposure of sentinel mice to wood shavings contaminated with excrement, to mimic a natural infection. Sentinel mice showed orthopoxvirus antibodies, and VACV DNA and infectious virus were detected in their faeces and intestines, even after six rounds of natural transmission. Together, these data suggest that murine excrement could play a relevant role in VACV spread and transmission, perhaps helping to explain how these viruses circulate between their natural hosts.
Assuntos
Modelos Animais de Doenças , Transmissão de Doença Infecciosa , Vaccinia virus/fisiologia , Vacínia/transmissão , Eliminação de Partículas Virais , Animais , Embrião de Galinha , Chlorocebus aethiops , Membrana Corioalantoide/virologia , DNA Viral/análise , DNA Viral/isolamento & purificação , Fezes/virologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase , Urina/virologia , Vacínia/patologia , Vacínia/virologia , Vaccinia virus/genética , Vaccinia virus/isolamento & purificação , Vaccinia virus/patogenicidade , Células VeroRESUMO
Avian paramyxovirus type 1, commonly referred to as Newcastle disease virus (NDV), is a serious pathogen of significant economic importance to the industry. To investigate the role of the fusion (F), hemagglutinin-neuraminidase (HN), and (P) phosphoprotein gene sequences in virulence, six strains of Newcastle disease virus (NDV) representing all pathotypes and seven recombinant strains created by reverse genetics were inoculated into 9-day-old chicken embryos. Tissues and chorioallantoic membranes (CAM) were harvested at 24-hour intervals post-inoculation. Riboprobe in situ hybridization and immunohistochemistry highlighted distinct tissue tropisms among the viruses. Presence of F and/or HN from virulent viruses inserted into lentogenic backbones caused dissemination of virus in a manner similar to wild type virulent viruses. Disruption of P gene decreased dissemination of velogeinic infectious clones. It is concluded that each of these genes contributes to pathogenicity.