RESUMO
Cowpox virus (CPXV) infection is a reportable and potentially zoonotic disease that occurs sporadically in a variety of animals. During the past six decades, CPXV infection has been extensively researched and described in both domestic (cat, dog, horse, cattle) and zoo animals (e. g. elephant, rhinoceros, okapi). Of note, a review of the literature produced only three reports of CPXV in individual or small groups of South American camelids. The goal of this review was to describe the current knowledge as it relates to clinical features of CPXV infection in South American camelids and to compare the clinical manifestations with those described in other animal species. In alpacas and llamas, virus transmission occurs via direct contact with infected animals or oronasal infection through microlesions in the skin and mucous membranes. In its mild form, the disease is limited to certain regions of the body (head, neck, extremities or perineal region) and characterised by pustules or crusts. CPXV infection can also cause generalised and frequently lethal disease with multifocal to diffuse skin lesions (papules, pustules, crusts, ulcers) accompanied by virus replication in other organs. Conjunctivitis, stomatitis and rhinitis are seen commonly together with nonspecific clinical signs, including anorexia, listlessness and fever. As in other poxvirus infections, factors leading to an immunosuppression may contribute to the development of the clinical ma -nifestation of CPXV infection. There appear to be no specific manifestations of CPXV infection in South American camelids. More research is needed to fully understand the pathogenesis and epidemio logy of CPXV infection, particularly in South American camelids.
Assuntos
Camelídeos Americanos/virologia , Vírus da Varíola Bovina/isolamento & purificação , Varíola Bovina/veterinária , Animais , Varíola Bovina/diagnóstico , Varíola Bovina/epidemiologia , Varíola Bovina/virologia , Pele/patologia , Pele/virologia , América do SulRESUMO
Vaccinia virus (VACV) has had an important role for humanity because of its use during the smallpox eradication campaign. VACV is the etiologic agent of the bovine vaccinia (BV), an emerging zoonosis that has been associated with economic, social, veterinary and public health problems, mainly in Brazil and India. Despite the current and historical VACV importance, there is little information about its circulation, prevalence, origins and maintenance in the environment, natural reservoirs and diversity. Brazilian VACV (VACV-BR) are grouped into at least two groups based on genetic and biological diversity: group 1 (G1) and group 2 (G2). In this study, we went to the field and investigated VACV clonal diversity directly from exanthemous lesions, during BV outbreaks. Our results demonstrate that the G1 VACV-BR were more frequently isolated. Furthermore, we were able to co-detect the two variants (G1 and G2) in the same sample. Molecular and biological analysis corroborated previous reports and confirmed the co-circulation of two VACV-BR lineages. The detected G2 clones presented exclusive genetic and biological markers, distinct to reference isolates, including VACV-Western Reserve. Two clones presented a mosaic profile, with both G1 and G2 features based on the molecular analysis of A56R, A26L and C23L genes. Indeed, some SNPs and INDELs in A56R nucleotide sequences were observed among clones of the same virus population, maybe as a result of an increased mutation rate in a mixed population. These results provide information about the diversity profile in VACV populations, highlighting its importance to VACV evolution and maintenance in the environment.
Assuntos
Varíola Bovina/virologia , Variação Genética , Vaccinia virus/classificação , Vaccinia virus/genética , Animais , Peso Corporal , Brasil/epidemiologia , Bovinos , Varíola Bovina/epidemiologia , Varíola Bovina/patologia , Modelos Animais de Doenças , Genótipo , Masculino , Camundongos Endogâmicos BALB C , Epidemiologia Molecular , Dados de Sequência Molecular , Análise de Sequência de DNA , Homologia de Sequência , Vaccinia virus/isolamento & purificação , VirulênciaRESUMO
The family Poxviridae comprises the most complex animal DNA viruses. During some poxvirus infections, A-type inclusion bodies (ATIs), codified by the ati gene, are produced. Although some studies have compared poxviruses that encode these inclusion bodies with those that do not, the biological function of ATIs is poorly understood. A recombinant ati-deleted cowpox virus was constructed and compared with the wild-type virus in in vitro experiments including electron microscopy and plaque and viral growth assays. No significant differences were observed in vitro. This reinforces the conclusion that the inclusion body is not essential for in vitro viral replication and morphogenesis. Additionally, different lesion progressions in vivo were observed by macroscopic and histological analysis, suggesting that the presence or absence of ATIs could result in different healing dynamics. This is the first time that the role of ATIs during viral replication has been studied based solely on one variable, the presence or absence of ATIs.
Assuntos
Vírus da Varíola Bovina/patogenicidade , Varíola Bovina/patologia , Varíola Bovina/virologia , Corpos de Inclusão/virologia , Animais , Chlorocebus aethiops , Varíola Bovina/genética , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Deleção de Sequência , Células Vero , Ensaio de Placa ViralRESUMO
The authors report three human cases of cowpox infection, among farm workers who were manually milking infected cows, in the microregion of Itajubá, Minas Gerais. The diagnostic techniques used were: isolation of samples similar to the vaccinia virus, from skin lesion secretions; polymerase chain reaction; electronic microscopy; and antibodies for Orthopoxvirus in the patients' blood.
Assuntos
Doenças dos Trabalhadores Agrícolas/diagnóstico , Varíola Bovina/diagnóstico , Vaccinia virus , Adulto , Doenças dos Trabalhadores Agrícolas/virologia , Animais , Anticorpos Antivirais/sangue , Bovinos , Varíola Bovina/virologia , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Vaccinia virus/genética , Vaccinia virus/imunologia , Vaccinia virus/ultraestruturaRESUMO
Os autores relatam três casos de varíola bovina em humanos, ordenhadores manuais em vacas infectadas, na microrregião de Itajubá, MG. As técnicas diagnósticas foram: isolamento de amostra semelhante ao vírus vaccinia de secreções das lesões cutâneas, reação em cadeia de polimerase, microscopia eletrônica e anticorpos para Orthopoxvirus no sangue dos pacientes.
The authors report three human cases of cowpox infection, among farm workers who were manually milking infected cows, in the microregion of Itajubá, Minas Gerais. The diagnostic techniques used were: isolation of samples similar to the vaccinia virus, from skin lesion secretions; polymerase chain reaction; electronic microscopy; and antibodies for Orthopoxvirus in the patients' blood.