Increased interleukin-10 associated with low IL-6 concentration correlated with greater survival rates in mice infected by rabies virus vaccinated against it and immunomodulated with P-acnes

Macrophage activity, cytokines serum concentration, serum neutralizing antibodies and lethality by rabies were evaluated in swiss mice experimentally infected with street rabies virus and submitted or not to antirabies vaccination and immunomodulation with P. acnes. Animals were killed at different times and serum was collected in order to evaluate cytokines concentration; peritonial and splenic macrophages were collected for macrophage activity evaluation. Greater survival rates higher IL-10 and low IL-6 serum concentration were observed in vaccinated animals treated using P. acnes. (C) 2004 Elsevier Ltd. All rights reserved.

Natural killer activity in mice infected with rabies virus and submitted to P-acnes (Propionibacterium acnes) as immunomodulator

The natural killer (NK) activity and lethality were evaluated in swiss mice experimentally infected with street rabies virus and submitted to immunomodulation by P. acnes (formerly Corynebacterium parvum). The infected animals were sacrificed at different times and spleen non-adherent cells were obtained through ficoll-hypaque gradient and depletion of glass-adherent cells. Immunosuppression was observed in rabies virus infected mice correlated with lower NK activity in clinically ill animals. Higher NK activity and percentual of survival were observed in the group submitted to P. acnes. The increased survival correlated with higher NK activity induced by P. acnes suggests a protective role of this natural barrier against rabies virus infection in mice. (C) 2000 Elsevier B.V. Ltd. All rights reserved.

Distribution of rabies virus in infected mice, vaccinated and submitted to P-acnes as immunomodulator

The lethality and distribution of rabies virus were evaluated in swiss mice experimentally infected with street rabies virus, vaccinated and submitted to immunomodulation by P. acnes (formerly Corynebacterium parvum). The animals were sacrificed at different times,when the different tissues were collected and submitted to fluorescent antibody test (FAT) and mouse inoculation test (MIT). The group submitted to vaccination and P. acnes treatment presented a percentage of survival superior to that observed in infected mice only treated with P. acnes. Control infected animals had the lowest survival rates. The distribution of rabies virus in spleen of infected mice, vaccinated and submitted to P. acnes was superior to that verified in infected mice not treated with P. acnes. The increased survival correlated with the distribution of rabies virus in lymphoid tissues, could be interpreted as the consequence of P. acnes activity on macrophages. The results suggest the role of macrophages against rabies virus infection in mice and the importance of vaccination in the post expositive treatment of rabies. (C) 2002 Published by Elsevier B.V. Ltd.

Ocorrência de anticorpos anti-Neospora caninum em cães da microrregião da Serra de Botucatu, Estado de São Paulo, Brasil

Neosporose é uma enfermidade parasitária causada pelo protozoário Neospora caninum reconhecido como importante causa de abortamento bovino e neuropatia canina. Considerando o isolamento de N. caninum e a sorologia freqüente em bovinos em nossa região, os objetivos do presente trabalho foram avaliar a ocorrência de anticorpos anti-N. caninum em cães da Microrregião da Serra de Botucatu, Estado de SãoPaulo, e sua associação ao sexo, idade e procedência quanto à zona urbana (exclusivamente cidade), rural (somente chácaras e sítios) e peri-urbana (acesso à zona urbana e rural) dos cães estudados. Foram analisados 963 cães, com ou sem raça definida, de ambos os sexos e diferentes idades, sem apresentação de qualquer sintomatologia clínica. Os animais foram selecionados aleatoriamente durante a campanha de vacinação anti-rábica da microrregião da Serra de Botucatu, no período de maio a setembro de 1998. O soro obtido dos animais foi avaliado por meio da Reação de Imunofluorescência Indireta (RIFI) utilizando como antígeno a cepa padrão NC-1 deN. caninum. Observaram-se 245 animais reagentes (25,4% de positividade), sendo 161 (27,5%) machos e, 84 (22,3%) fêmeas. Dos animais de zona urbana, rural e mista 223 (25,8%),11(16,9%) e 11(33,3%), respectivamente, foram reagentes à prova de RIFI. Todos os 11 municípios apresentaram cães soropositivos com valores de ocorrência que variaram de 8,9% a 53,5%. Observou-se percentual de positividade menor em cães até um ano (16,2%) quando comparados àqueles entre 1 a 4 anos e superior a 4 anos (28,4 % e 28,0%, respectivamente) que não apresentaram diferença entre si. Os resultados obtidos caracterizaram soropositividade para N. caninum em cães pertencentes a todos os municípios da Microrregião da Serra de Botucatu evidenciando a ampla distribuição do agente na região.

Epidemiology of leptospirosis at Sorocaba Zoo, São Paulo state, Southeastern Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Epidemiology, clinical signs, histopathology and molecular characterization of canine leproid granuloma: a retrospective study of cases from Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevance of Budgerigars (Melopsittacus undulatus) in Experimental Epidemiology of Newcastle Disease.

This study was carried out to clarify the real role that was played by the budgerigars (Melopsittacus undulatus) in the epidemiological plan, under the perspective of its being an infection source of the Newcastle Disease Virus (NDV). For this, the study used Specific-Pathogen-Free chicks (SPF) that were housed with budgerigars that were inoculated with a pathogenic strain (velogenic viscerotropic) of NDV (EID5o =10815/0.1 mL) pathogenic to chickens, by the ocular-nasal via. Each group was composed by 10 SPF chicks and 5 budgerigars. After 5 days of the inoculation of the budgerigars with NDV, SPF chicks were put together with each group of budgerigars, so that there was a direct contact between both species. Cloaca) swabs and blood samples were collected in both species (budgerigars and SPF chicks) after 13 and 19 days post-challenge, respectively, for genome viral excretion by Reverse Transcription Polymerase Chain Reaction (RTPCR) and antibody's search by the inhibition of hemmaglutination test (HI). Budgerigars did not demonstrate any clinical signs of Newcastle Disease (ND). They were refractory to the clinical disease with the NDV. However, antibody titres from inhibition of Hemagglutination (HI) test were detected 9 and 21 days after challenge. Therefore, it was demonstrated the state of carrier of NDV in this species. In SPF chicks allocated with infected budgerigars, NDV genome was detected 13 and 19 days after challenge. Thus, the transmission of the pathogenic virus from the budgerigars to SPF chicks that were housed together was evident until 19 days of the experimental infection with this pathogen. This reveals the importance of the budgerigars from the epidemiological point of view as a potential source of infection of the NDV to commercial chickens that could be raised near this species.

Rabies virus in a pregnant naturally infected southern yellow bat (Lasiurus ega)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Vaccine immune response and interference of colostral antibodies in calves vaccinated against rabies at 2, 4 and 6 months of age born from antirabies revaccinated females

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Exposure to rabies virus in a population of free-ranging capuchin monkeys (Cebus apella nigritus) in a fragmented, environmentally protected area in southeastern Brazil

The aim of this study is to assess the frequency of rabies antibodies in free-ranging capuchin monkeys (Cebus apella nigritus) in a fragmented, environmentally protected, rural area of southeastern Brazil. Thirty-six free-ranging monkeys were tested by the rapid fluorescent focus inhibition test for detection of antibodies against rabies virus. Four individuals (11.11 %) had neutralizing antibody titers a parts per thousand yen0.25 IU/mL, demonstrating rabies virus exposure.

Association between handling stress in the corral and rabies antibody titers in selenium-supplemented cattle

This study determined the correlation between serum cortisol levels and rabies antibody titers in cattle primo-vaccinated against rabies and supplemented with dietary selenium (Se). Sixty Nelore male calves (10 to 12 months old) received daily and individual dietary supplementation with 0, 3.6, 5.4 and 6.4 mg Se (groups Gc, G(3.6), G(5.4) and G(6.4), respectively). The animals were vaccinated against rabies (day 0) and subjected to handling stress in the corral for 120 days. Blood sampling procedures were performed on days 0, 15, 30, 60, 90 and 120. Cortisol levels increased until day 90, but had dropped significantly by day 120 (P < 0.01). Rabies antibody titers on days 30 and 90 were similar among Se-supplemented groups; in the control group, rabies antibodies decreased significantly from day 30 to 60, and 90 to 120. Serum cortisol levels and antibody titers were not correlated in most of the groups or blood sampling days. A positive correlation among these variables was found only in G(6.4) on days 60 (R = 0.513; P = 0.05) and 120 (R = 0.644; P = 0.009). In conclusion, repeated handling in the corral stresses cattle, but without compromising rabies humoral immune response.

Efficiency of Matricaria chamomilla CH12 and number of doses of rabies vaccine on the humoral immune response in cattle

This study evaluated the effect of Matricaria chamomilla and vaccination frequency on cattle immunization against rabies. Four groups (n = 15/group) were treated with or without Matricaria chamomilla CH12 and vaccinated with one or two doses of rabies vaccine (30 day interval). No effect of chamomile was found on cattle immunization against rabies; however, antibody titers were protective in cattle vaccinated twice, while 93.3% of cattle vaccinated only once had titers under 0.5 UI/ml after 60 days. In conclusion, the use of chamomile did not alter the Immoral immune response in cattle, and two vaccine doses are suggested for achieving protective antibody titers.

Wild rabies virus detection by plaque assay from naturally infected brains in different species

A simple, sensitive and specific plaque assay protocol for the detection of wild type rabies virus in different species is described using confluent monolayers of chicken embryo cells in 6-well plates. Plaques are produced after application of either agarose or Sephadex G-100 overlay onto cell monolayers and incubation for 96 h after virus infection at 37 degreesC. The parameters affecting plaque appearance include cell seeding concentration, overlay composition and time of incubation after infection. Optimal conditions are seeding at a concentration of 4 x 10(6) cell/cm(3), incubation at 37 degreesC in 5% CO2 atmosphere during 96 h, using either 1% agarose or 2% Sephadex G-100 overlays. The described plaque assay would be a new valuable too] in conducting various quantitative investigations, since the chicken embryo cells are susceptible to rabies virus infection from all species studied. (C) 2004 Elsevier B.V. All rights reserved.

Chicken embryo related (CER) cell line for quantification of rabies neutralizing antibody by fluorescent focus inhibition test

Levels of rabies virus neutralization antibody in sera from vaccinated dogs and cattle were either measured by mouse neutralization test (MNT) or by rapid fluorescent focus inhibition test (RFFIT), performed on CER monolayers. The two tests were compared for their ability to detect the 0.5 International Units/ml (I.U.) recommended by the World Health Organization (WHO) as the minimum response for proof of rabies immunization. A significant correlation was found between the two tests (n = 211; r = 0.9949 in dogs and 0.9307 in cows, p < 0.001), good sensitivity (87.5%), specificity (94.7%) and agreement (96.6%) as well. RFFIT method standardized on CER cell system for neutralizing antibodies detection turns the diagnosis easier and less expensive, specially when a great number of samples must be tested from endemic areas as commonly found in Brazil. (c) 2005 the International Association for Biologicals. Published by Elsevier Ltd. All rights reserved.