Fabiana Magalhães Coelho

Feline Immunodeficiency Virus Subtype B in Domestic Cats in Minas Gerais, Brazil

Feline immunodeficiency virus (FIV) was isolated in 1986 from a feline leukaemia virusnegative cat with chronic opportunistic infections (Pedersen et al., 1987). Clinical signs most frequently observed in FIV infection are stomatitis, gingivitis, anaemia and neurological dysfunctions (Ishida et al., 1989; Yamamoto et al., 1989). Epidemiological surveys conducted in several parts of the world revealed that the prevalence of FIV infection in cats varies from 1% to 15% in healthy cats and from 3% to 44% in sick cats (Sukura et al., 1992; Ueland and Lutz, 1992). FIV strains isolated from domestic cats have been classified into five subtypes, designated A, B, C, D and E, by comparing nucleotide sequences of region V3–V5 of the env gene (Sodora et al., 1994; Kakinuma et al., 1995; Pecoraro et al., 1996), and similar results were also obtained when the nucleotide sequences of the gag gene were analysed (Kakinuma et al., 1995). The aim of this survey was to detect and subtype of FIV strains circulating in Minas Gerais (MG), Brazil.

Naturally occurring feline leukemia virus subgroup A and B infections in urban domestic cats

A nested-PCR (n-PCR) was used to detect feline leukemia virus (FeLV) proviral DNA in blood samples from 464 sick and 608 healthy domestic cats (Felis catus) selected by convenience, and a significantly high prevalence of FeLV infection was observed. n-PCR results revealed the presence of FeLV proviral DNA in 47.2 % of sick cats and 47.4 % of healthy cats. Phylogenetic analysis revealed that FeLV samples from healthy or sick cats were grouped into separate clades. We determined FeLV subgroups by an n-PCR based on the envelope (env) gene. The partial env gene of FeLV Minas Gerais (MG) samples were compared to various exogenous FeLV isolates and endogenous (enFeLV) provirus from the same region. FeLV-B MG samples were more similar to endogenous sequences and to natural FeLV-B isolates than to either FeLV-A or FeLV-C. The results revealed the circulation of FeLV-B in large populations of urban domestic cats in Brazil.

Survey of Feline Leukemia Virus and Feline Coronaviruses in Captive Neotropical Wild Felids from Southern Brazil

Abstract A total of 57 captive neotropical felids (one Leopardus geoffroyi, 14 Leopardus pardalis, 17 Leopardus wiedii, 22 Leopardus tigrinus, and three Puma yagouaroundi) from the Itaipu Binacional Wildlife Research Center (Refúgio Bela Vista, Southern Brazil) were anesthetized for blood collection. Feces samples were available for 44 animals, including one L. geoffroyi, eight L. pardalis, 14 L. wiedii, 20 L. tigrinus, and one P. yagouaroundi. Total DNA and RNA were extracted from blood and feces, respectively, using commercial kits. Blood DNA samples were evaluated by polymerase chain reaction (PCR) for feline leukemia virus (FeLV) proviral DNA, whereas reverse transcriptase–PCR was run on fecal samples for detection of coronavirus RNA. None of the samples were positive for coronaviruses. A male L. pardalis and a female L. tigrinus were positive for FeLV proviral DNA, and identities of PCR products were confirmed by sequencing. This is the first evidence of FeLV proviral DNA in these species in Southern Brazil.

Neurological disorder in cattle associated with bovine herpesvirus 4

A nested PCR assay was used to diagnose bovine encephalitis through herpesviruses including bovine herpesvirus 5 (BHV-5), bovine herpesvirus 1 (BHV-1), Aujeszkys disease virus (SHV-1), and ovine herpesvirus 2 (OHV-2) in 14 fragments of central nervous system (CNS) from cattle that died with neurological signs. In addition, as some samples of bovine herpesvirus type 4 (BHV-4) have been isolated from neural tissue, it was also tested by nested PCR. The cases of encephalitis occurred in isolation at different times of the year and did not present any seasonality. The duration of the clinical course ranged between 1 to 15 days, and in 64.3% of the cases it manifested between 1 to 2 days. The most frequently observed neurological signs were ataxia, recumbency, unsteadiness and inability to stand, opisthotonus, paddling movements, nystagmus and ptyalism. In the nested assay, there was no evidence of: BHV-1, SHV-1 or OHV-2 in the DNA obtained from the CNS in any of the samples. But the presence of BHV-4 was found in all fragments of the CNS in cattle which died presenting neurological signs. Moreover, BHV-5 was found in association with BHV-4 in two of these samples.

Phylogenetic analysis of feline immunodeficiency virus strains from State of Minas Gerais, Brazil

A regiao p17-p24 do gene gag de 10 amostras do virus da imunodeficiencia felina detectadas no estado de Minas Gerais (Brasil) foi sequenciada com o objetivo de determinar a sua classificacao molecular e a sua relacao com sequencias de amostras previamente descritas. As amostras pertenciam ao subtipo B, entretanto foi possivel observar que a maioria delas encontra-se em um subgrupo dentro do subtipo B, o que indica presenca de um possivel ancestral comum entre elas.

Concomitant helminth infection downmodulates the Vaccinia virus-specific immune response and potentiates virus-associated pathology.

The aim of this work was to elucidate the immunopathological mechanisms of how helminths may influence the course of a viral infection, using a murine model. Severe virulence, a relevant increase in the virus titres in the lung and a higher mortality rate were observed in Ascaris and Vaccinia virus (VACV) co-infected mice, compared with VACV mono-infected mice. Immunopathological analysis suggested that the ablation of CD8+ T cells, the marked reduction of circulating CD4+ T cells producing IFN-γ, and the robust pulmonary inflammation were associated with the increase of morbidity/mortality in co-infection and subsequently with the negative impact of concomitant pulmonary ascariasis and respiratory VACV infection for the host. On the other hand, when evaluating the impact of the co-infection on the parasitic burden, co-infected mice presented a marked decrease in the total number of migrating Ascaris lung-stage larvae in comparison with Ascaris mono-infection. Taken together, our major findings suggest that Ascaris and VACV co-infection may potentiate the virus-associated pathology by the downmodulation of the VACV-specific immune response. Moreover, this study provides new evidence of how helminth parasites may influence the course of a coincident viral infection.

Identification and isolation of psittacid herpesvirus from psittacids in Brazil.

Psittacid herpesvirus (PsHV) was isolated from 41 birds kept in captivity in Belo Horizonte, Minas Gerais/Brazil using chicken embryo fibroblasts (CEF) cell cultures. For this study, leukocytes or cloacal swabs of live birds were used. Also, portions of liver, spleen or kidney from birds collected at necropsy were utilized for these tests. PCR tests confirmed the presence of PsHV in 100% of samples. Thirty-three of the PCR products were sequenced and the results disclosed a 99% and 100% identity when compared with other sequences PsHV-1 (AY372243.1 and AF261756.1), previously deposited in GenBank. In addition, histopathology was performed and 19 of the 29 birds contained random multifocal lymphoplasmacytic hepatitis with necrotic foci, suggestive of viral infection. Three samples were examined by electron microscopy to visualize the viral particles obtained from cell culture. The viral structures measured 269 nm in average, had envelopes with an icosahedral capsid and tegument, consistent with herpesvirus. Thus, a total of 41 isolates were obtained from PsHV cell cultivation in CEF, confirming the circulation of the virus between parrots kept in captivity in Belo Horizonte, and affirming the importance of further studies in this area.

Equine coital exanthema in a stallion

Em agosto de 2008, um garanhao da raca Mangalarga Marchador, de quatro anos de idade, com historico clinico de apatia, inapetencia e edema de prepucio e escroto, apresentou, ao exame clinico, exsudato purulento fluindo pelo ostio prepucial, prepucio e mucosa peniana com inumeras lesoes circulares de bordos elevados e hiperemicos, centro ulcerado recoberto por material amarelado de aspecto fibrinoso, com distribuicao multifocal. Histologicamente, a mucosa peniana apresentou areas de ulceracao associadas a infiltrado inflamatorio misto, com necrose multifocal e moderado acumulo de fibrina, que se estendiam para o tecido conjuntivo adjacente. O diagnostico morfologico foi de balanopostite ulcerativa fibrino-necrotica multifocal intensa, similar ao encontrado em casos de exantema coital equino (ECE), causado pelo herpesvirus equino 3 (EHV-3). Amostra de pele do prepucio e sangue, colhido em EDTA, foram submetidos a ensaios de PCR especificos para EHV-3, observando-se a amplificacao de um produto de tamanho esperado de 518pb. A deteccao do EHV-3 foi confirmada por meio de seu sequenciamento, sendo a sequencia de nucleotideos depositada no GenBank sob o numero GQ336877. As sequencias de nucleotideos e as de aminoacidos deduzidos apresentaram identidade de 99% e 100%, respectivamente, com a sequencia de EHV-3 disponivel no GenBank, numero AF081188. Apos 15 dias de tratamento, houve completa cicatrizacao das lesoes, com despigmentacao da pele, principalmente, no prepucio e na bolsa escrotal. Com base nos achados clinicos, histopatologicos, PCR e sequenciamento, concluiu-se tratar de um caso de exantema coital equino, sendo o primeiro com confirmacao definitiva do agente etiologico no Brasil.

Ocorrência do vírus da leucemia felina em Felis cattus em Belo Horizonte

Blood samples from 1,072 domestic cats of nine administrative regions of Belo Horizonte, MG, were collected and tested using PCR nested for the occurrence of feline leukemia virus (FeLV). Overall occurrence was 47.5% (507/1072) being North (68.1%) and East (54.4%) the most prevalent areas. Epidemiological data showed that FeLV infection was very common among examined cats and breed neither gender nor were predisposing factors for FeLV. The results suggest that the agglomeration of a large number of cats in the same environment can be an important factor for the increase in the rate of transmission of this retrovirus among domestic cats in the studied city.

Genotypic characterization of psittacid herpesvirus isolates from Brazil

Thirty-six isolates of psittacid herpesvirus (PsHV), obtained from 12 different species of psittacids in Brazil, were genotypically characterized by restriction fragment length polymorphism (RFLP) analysis and PCR amplification. RFLP analysis with the PstI enzyme revealed four distinct restriction patterns (A1, X, W and Y), of which only A1 (corresponding to PsHV-1) had previously been described. To study PCR amplification patterns, six pairs of primers were used. Using this method, six variants were identified, of which, variants 10, 8, and 9 (in this order) were most prevalent, followed by variants 1, 4, and 5. It was not possible to correlate the PCR and RFLP patterns. Twenty-nine of the 36 isolates were shown to contain a 419 bp fragment of the UL16 gene, displaying high similarity to the PsHV-1 sequences available in GenBank. Comparison of the results with the literature data suggests that the 36 Brazilian isolates from this study belong to genotype 1 and serotype 1.