Nota técnica sobre esquema de profilaxia da raiva / Technical note on rabies prophylaxis scheme

Critérios para esquema de prevenção de raiva no Estado do Tocantins. Controle sorológico. Restrito a pessoas com risco de exposição permanente ao vírus da raiva, como: Médicos veterinários, técnicos da Agência de Defesa Agropecuária, biólogos, funcionários do Naturatins que atuam em captura de mamíferos silvestres, espeleólogos.

Criteria for a rabies prevention scheme in the State of Tocantins. Serological control. Restricted to people at risk of permanent exposure to the rabies virus, such as: Veterinarians, technicians from the Agricultural Defense Agency, biologists, Naturatins employees who work in capturing wild mammals, cavers.

Criterios para un plan de prevención de la rabia en el estado de Tocantins. Control serológico. Restringido a personas en riesgo de exposición permanente al virus de la rabia, tales como: Veterinarios, técnicos de la Agencia de Defensa Agrícola, biólogos, empleados de Naturatins que trabajan en la captura de mamíferos silvestres, espeleólogos.

Rabies in Callithrix sp. in the urban area of Niterói, Rio de Janeiro, Brazil

Abstract In Brazil, rabies occurs mainly within an urban cycle, in which dogs and bats are reservoirs. This paper aims to report the occurrence of rabies in Callithrix sp. in Niterói, Rio de Janeiro, Brazil. In June 2019 a hybrid specimen was referred for diagnosis. The Direct Fluorescent Antibody, Mouse Inoculation, and Polymerase Chain Reaction tests were positive. A phylogenetic analysis was compatible with antigenic variant 3, characteristic of Desmodus rotundus. New studies should be undertaken to elucidate the real role of callitrichids in the urban rabies cycle.

Rabies virus monitoring in bat populations in Rondônia state, Brazil

Abstract INTRODUCTION: The Jirau hydroelectric power plant built in Rondônia state has environmental impacts that could be relevant to rabies outbreaks. METHODS: Bat populations were monitored for rabies by fluorescent antibody testing and simplified fluorescent inhibition microtesting between 2010 and 2015. RESULTS: All 1,183 bats tested negative for rabies. The prevalence of rabies antibodies was 17.5% in 1,049 bats. CONCLUSIONS: The rabies antibody dosage was not reactive in samples collected before the environmental changes, and there was a progressive increase in subsequent collections that could indicate an increase in rabies virus circulation among bats and risk of a rabies outbreak.

Low level of the immune response against rabies virus in dogs and cats, a cross-sectional study in sheltered animals, Santander, Colombia / Baixo nível de resposta imune contra o vírus da raiva em cães e gatos, um estudo transversal em animais abrigados, Santander, Colombia

Rabies is an incurable and fatal progressive viral encephalomyelitis that causes approximately 61,000 deaths a year globally mainly by dog bites, which show the importance of anti-rabies vaccination in dogs to achieve elimination of the disease. In Colombia, multiple cases of human rabies transmitted by dogs and cats have been reported since 1999, showing an increased significance of cats in the transmission of rabies, mainly in rabies of wild origin. Therefore, the aim of the present study was to evaluate the development of neutralizing antibodies in dogs and cats during the mass vaccination campaign of the second half of 2015 in the city of Bucaramanga. For this purpose, a descriptive cross-sectional study with convenience sampling was conducted in 382 dogs and cats (295 dogs, 87 cats), and an evaluation of the humoral immune response of the animals was performed by quantitative ELISA. The prevalence of optimal neutralizing antibodies (>0.5 IU/ml) was only 32.76% (95% CI=28.05-37.46%) in the entire population studied and most of the animals did not have an adequate response to the vaccination, or seroconversion was not detected on them (65.45-95% confidence interval, CI=60.68-70.21%). Significant difference was found between the neutralizing antibody titers in cats and dogs, with a higher neutralizing response in cats. In conclusion, although mass vaccination campaigns for dogs and cats are the most important measure to interrupt virus circulation among the animals, achievement of a good neutralizing immune response in the animals is useful to demonstrate that vaccination has been successful, allowing the maintenance of the required minimum levels of population immunity. These results will allow the implementation of corrective measures in Bucaramanga to achieve better seroconversion rates. Other cities are expected to implement similar seroconversion assessments to verify the quality of effective anti-rabies vaccination in animal populations.(AU)

A raiva é uma encefalomielite viral progressiva incurável e fatal que causa aproximadamente 61.000 mortes por ano no mundo, principalmente por mordidas de cães, que mostram a importância da vacinação anti-rábica em cães para conseguir a eliminação da doença. Na Colômbia, vários casos de raiva humana transmitida por cães e gatos foram relatados desde 1999, mostrando um aumento na importância de gatos na transmissão da raiva, principalmente em raiva de origem selvagem. Portanto, o objetivo do presente estudo foi avaliar o desenvolvimento de anticorpos neutralizantes em cães e gatos durante a campanha de vacinação em massa do segundo semestre de 2015 na cidade de Bucaramanga. Para este propósito, um estudo descritivo transversal com amostragem de conveniência foi realizado em 382 cães e gatos (295 cães, 87 gatos), e uma avaliação da resposta imune humoral dos animais foi realizada por ELISA quantitativo. A prevalência de anticorpos neutralizantes ótimos (>0,5 UI/ml) foi de apenas 32,76% (IC 95% = 28,05-37,46%) em toda a população estudada e a maioria dos animais não teve resposta adequada à vacinação, ou a soroconversão foi não detectado neles (65,45-95% intervalo de confiança IC = 60,68-70,21%). Diferença significativa foi encontrada entre os títulos de anticorpos neutralizantes em gatos e cães, com uma maior resposta neutralizante em gatos. Em conclusão, embora as campanhas de vacinação em massa para cães e gatos sejam a medida mais importante para interromper a circulação do vírus entre os animais, a obtenção de uma boa resposta imunológica neutralizante nos animais é útil para demonstrar que a vacinação foi bem sucedida, permitindo a manutenção necessária dos níveis mínimos de imunidade da população. Esses resultados permitirão que a implementação de medidas corretivas em Bucaramanga alcance melhores taxas de soroconversão. Outras cidades devem implementar avaliações similares de soroconversão para verificar a qualidade da vacinação anti-rábica efetiva em populações animais.(AU)

Comparative analysis of Mouse Inoculation Test and Virus Isolation in Cell Culture for rabies diagnosis in animals of Parana, Brazil

Abstract INTRODUCTION: Rabies is an acute zoonotic disease, caused by a rhabdovirus that can affect all mammals, and is commonly transmitted by the bite of a rabid animal. The definitive diagnosis is laboratorial, by the Fluorescent Antibody Test (FAT) as a quick test and Mouse Inoculation Test (MIT) as a confirmatory test (gold standard). Studies conducted over the past three decades indicate that MIT and Virus Isolation in Cell Culture (VICC) can provide the same effectiveness, the latter being considered superior in bioethics and animal welfare. The aim of this study was to compare VICC with MIT, in terms of accuracy, biosafety and occupational health, supply and equipment costs, bioethics and animal welfare, in a Brazilian public health lab. METHODS: We utilized 400 samples of animal neurological tissue to compare the performance of VICC against MIT. The variables analyzed were accuracy, biosafety and occupational health, time spent in performing the tests, supply and equipment costs, bioethics and animal welfare evaluation. RESULTS: Both VICC and MIT had almost the same accuracy (99.8%), although VICC presented fewer risks regarding biosafety and mental health of the technicians, and reduced time between inoculation and obtaining the results (approximately 22 days less). In addition, VICC presented lower supply costs (86.5% less), equipment costs (32.6% less), and the advantage of not using animals. CONCLUSIONS: These results confirm that VICC can replace MIT, offering the same accuracy and better features regarding cost, results, biosafety and occupational health, and bioethics and animal welfare.

Survival of a newborn from a pregnant woman with rabies infection

Rabies is very common in Peoples Republic of China. Each year thousands of people die because of this disease, but rabies diagnosed in pregnancy is very rare. Case Presentation In this study, we report the case of a pregnant woman who was infected with the rabies virus after a dog bite. The symptoms of rabies appeared in labor and she died after pregnancy. Her baby and husband did not develop the disease. Conclusion The phenomenon that the newborn infant was healthy may be related to the protective role of placenta in resisting the invasion of the rabies virus or the absence of systemic viremia. The prompt administration of vaccines and anti-rabies immunoglobulin to the infant may have also contributed to his survival.

VIROLOGICAL AND SEROLOGICAL DIAGNOSIS OF RABIES IN BATS FROM AN URBAN AREA IN THE BRAZILIAN AMAZON / Diagnóstico virológico e sorológico de raiva em morcegos de uma área urbana na Amazônia Brasileira

The outbreaks of rabies in humans transmitted by Desmodus rotundus in 2004 and 2005, in the northeast of the Brazilian State of Para, eastern Amazon basin, made this a priority area for studies on this zoonosis. Given this, the present study provides data on this phenomenon in an urban context, in order to assess the possible circulation of the classic rabies virus (RABV) among bat species in Capanema, a town in the Amazon basin. Bats were collected, in 2011, with mist nets during the wet and dry seasons. Samples of brain tissue and blood were collected for virological and serological survey, respectively. None of the 153 brain tissue samples analyzed tested positive for RABV infection, but 50.34% (95% CI: 45.67-55.01%) of the serum samples analyzed were seropositive. Artibeus planirostris was the most common species, with a high percentage of seropositive individuals (52.46%, 95% CI: 52.31 52.60%). Statistically, equal proportions of seropositive results were obtained in the rainy and dry seasons (c2 = 0.057, d.f. = 1, p = 0.88). Significantly higher proportions of males (55.96%, 95% CI: 48.96-62.96%) and adults (52.37%, 95% CI: 47.35-57.39%) were seropositive. While none of the brain tissue samples tested positive for infection, the high proportion of seropositive specimens indicates that RABV may be widespread in this urban area.

Os surtos de raiva em humanos transmitida por Desmodus rotundus em 2004 e 2005 no nordeste do estado do Pará, Brasil, Amazônia Oriental, fizeram desta uma área prioritária para estudos sobre essa zoonose. Diante disso, o presente estudo fornece dados sobre esse fenômeno em contexto urbano, afim de avaliar uma possível circulação do vírus clássico da raiva (RABV) entre espécies de morcegos em Capanema, cidade localizada na bacia Amazônica. Os morcegos foram coletados em 2011, com auxílio de redes de espera durante as estações seca e chuvosa. Amostras de encéfalo e de sangue foram coletadas para o diagnóstico virológico e sorológico, respectivamente. Das 153 amostras de encéfalo analisadas, nenhuma encontrou-se positiva para infecção pelo RABV, porém, 50,34% (95% CI: 45,67-55,01) das amostras de soro analisadas estavam soropositivas. Artibeus planirostris foi a espécie mais comum, e seu percentual de indivíduos soropositivos foi bem elevado (52.46%, 95% CI: 52,31-52,60). Porções estatisticamente iguais de soropositivos foram registrados nas estações (c2 = 0,057, d.f. = 1, p = 0,88). Uma porção significativamente elevada de machos (55,96%, 95% CI: 48,96%-62,96%), e adultos (52,37%, 95% CI: 47,35%-57,39%) foram soropositivos. Apesar de nenhuma das amostras de encéfalo terem sido positivas para raiva, a alta proporção de espécimes soropositivos indica uma possível circulação do RABV nessa área urbana.

Evaluation of short-interfering RNAs treatment in experimental rabies due to wild-type virus

ABSTRACTWe have evaluated the efficacy of short-interfering RNAs targeting the nucleoprotein gene and also the brain immune response in treated and non-treated infected mice. Mice were inoculated with wild-type virus, classified as dog (hv2) or vampire bat (hv3) variants and both groups were treated or leaved as controls. No difference was observed in the lethality rate between treated and non-treated groups, although clinical evaluation of hv2 infected mice showed differences in the severity of clinical disease (p = 0.0006). Evaluation of brain immune response 5 days post-inoculation in treated hv2 group showed no difference among the analyzed genes, whereas after 10 days post-inoculation there was increased expression of 2',5'-oligoadenylate synthetase 1, tumor necrosis factor alpha, interleukin 12, interferon gamma, and C-X-C motif chemokine 10 associated with higher expression of Ngene in the same period (p < 0.0001). In hv2 non-treated group only higher interferon beta expression was found at day 5. The observed differences in results of the immune response genes between treated and non-treated groups is not promising as they had neither impact on mortality nor even a reduction in the expression of N gene in siRNA treated animals. This finding suggests that the use of pre-designed siRNA alone may not be useful in rabies treatment.

Rabies surveillance in bats in Northwestern State of São Paulo

Introduction Rabies is an important zoonosis that occurs in mammals, with bats acting as Lyssavirus reservoirs in urban, rural and natural areas. Rabies cases in bats have been recorded primarily in urban areas in Northwestern State of São Paulo since 1998. This study investigated the circulation of rabies virus by seeking to identify the virus in the brain in several species of bats in this region and by measuring rabies-virus neutralizing antibody levels in the hematophagous bat Desmodus rotundus. Methods From 2008 to 2012, 1,490 bat brain samples were sent to the Universidade Estadual Paulista (UNESP) Rabies Laboratory in Araçatuba, and 125 serum samples from vampire bats that were captured in this geographical region were analyzed. Results Rabies virus was detected in the brains of 26 (2%) of 1,314 non-hematophagous bats using the fluorescent antibody test (FAT) and the mouse inoculation test (MIT). None of the 176 hematophagous bat samples were positive for rabies virus when a virus detection test was utilized. Out of 125 vampire bat serum samples, 9 (7%) had levels of rabies virus neutralization antibodies (RVNAs) that were higher than 0.5IU/mL; 65% (81/125) had titers between 0.10IU/mL and 0.5IU/mL; and 28% (35/125) were negative for RVNAs using the simplified fluorescent inhibition ...

Comparison of a modified shell vial culture procedure with conventional mouse inoculation for rabies virus isolation

Rabies is a neurotropic disease that is often lethal. The early diagnosis of rabies infection is important and requires methods that allow for the isolation of the virus from animals and humans. The present study compared a modified shell vial (MSV) procedure using 24-well tissue culture plates with the mouse inoculation test (MIT), which is considered the gold standard for rabies virus isolation. Thirty brain samples (25 positive and 5 negative by the fluorescent antibody test) obtained from different animal species at the National Institute of Hygiene Rafael Rangel in Caracas, Venezuela, were studied by the MIT and MSV assays. Nine samples (36%) were positive at 24 h, 10 (40%) were positive at 48 h and six (24%) were positive at 72 h by the MSV assay. With the MIT assay, 76% were positive at six days post inoculation and 12% were positive at 12 and 18 days post inoculation. One sample that was negative according to the MSV assay was positive with MIT on the 12th day. The MSV procedure exhibited a sensitivity of 96.2%, a specificity of 100%, a positive predictive value of 100% and a negative predictive value 80%. This procedure allowed for rapid rabies virus detection. MIT can be employed as an alternative method in laboratories without tissue culture facilities.

Frequency and causes for exclusion from randomization of healthy volunteers screened for a phase 1 study in India.

Background. Only a proportion of screened potential participants were actually randomized while conducting a phase 1 study of a humanized rabies monoclonal antibody. We aimed to assess the challenges in defining who is a normal volunteer and the issues that affect volunteer recruitment and thus accrual. Methods. One hundred and fifty-six volunteers were screened and 74 (47.4%) were randomized in a phase 1 study. Data on all participants screened for the study were analysed and reasons for their non-randomization were classified. Results. The reasons for volunteers not being randomized were: (i) deranged laboratory parameters (n=62); (ii) nonlaboratory causes (n=4); and (iii) withdrawal of consent (n=16). A large proportion of screen failures were due to low haemoglobin levels, which led to the protocol being amended midway during the study. An informal interview of those who declined consent showed that they had only wanted to get themselves investigated thoroughly or were interested in getting their HIV status evaluated. Conclusions. Our study shows that <50% participants screened for a phase 1 study in a developing country actually get randomized. The main reason for non-randomization is abnormal laboratory tests. This may help investigators and sponsors to plan protocols better, define normal ranges with acceptable variations based on their own populations a priori and have more pragmatic accrual targets.

Molecular characterization of rabies virus isolated from non-haematophagous bats in Brazil / Caracterização molecular do vírus da raiva isolado de morcegos não-hematófagos no Brasil

INTRODUCTION: Rabies is an important zoonosis that causes thousands of deaths worldwide each year. Although the terrestrial cycle, mainly transmitted by dogs, is controlled in Brazil, the aerial cycle remains a serious public health issue, besides the economic problem. In the aerial cycle, the haematophagous bat Desmodus rotundus is the main source of infection, where several different species of non-haematophagous bats can be infected and can transmit the virus. METHODS: The aim of this work was to study the epidemiological pattern of rabies using antigenic characterization with monoclonal antibodies and genetic characterization by reverse-transcriptase polymerase chain reaction followed by sequencing and phylogenetic analysis of non-haematophagous bats' and herbivorous animals' central nervous system samples from the western region of the State of São Paulo, Brazil. RESULTS: From 27 samples, 3 antigenic variants were identified: AgV-3, AgV-4, and AgV-6; and from 29 samples, 5 different clusters were identified, all belonging to the rabies virus species. CONCLUSIONS: Although only non-haematophagous bats were evaluated in the studied region, the majority of samples were from antigenic and genetic variants related to haematophagous bats Desmodus rotundus. Samples from the same antigenic variant were segregated in more than one genetic cluster. This study demonstrated the diversity of rabies virus genetic lineages presented and circulating in non-haematophagous bats in the studied region.

INTRODUÇÃO: A raiva é uma importante zoonose responsável por milhares de mortes anualmente em todo o mundo. Embora o ciclo silvestre, onde os cães são os principais transmissores esteja controlado no Brasil, o ciclo aéreo, onde o morcego hematófago Desmodus rotundus é o principal transmissor e diversas espécies de morcegos não hematófagos podem se infectar e transmitir o vírus, permanence como um importante problema econômico e de saúde pública. MÉTODOS: O objetivo deste trabalho foi a caracterização antigênica por meio da utilização de anticorpos monoclonais e a caracterização genética por meio da reação em cadeia pela polimerase pela transcriptase reversa seguida de análise filogenética em morcegos não hematófagos e animais domésticos herbívoros provenientes da região oeste do Estado de São Paulo. RESULTADOS: A análise antigênica de 27 amostras determinou três variantes distintas: Agv-3, AgV-4 e AgV-6; a análise genética de 29 amostras identificou 5 diferentes grupos, todos pertencentes a espécie Rabies virus. CONCLUSÕES: Ainda que apenas amostras de morcegos não hematófagos tenham sido analisadas, a maioria das variantes antigênicas e genéticas identificadas na região estava relacionada com a variante mantida pelos morcegos hematófagos Desmodus rotundus. Amostras de uma mesma variante antigênica segregaram em mais de um clado genético. Este estudo demonstrou a diversidade de linhagens genéticas do vírus da raiva presentes e circulantes em morcegos não hematófagos na região estudada.

Risco de transmissão do vírus da raiva oriundo de sagui (Callithrix jacchus), domiciliado e semidomiciliado, para o homem na região metropolitana de Fortaleza, estado do Ceará / Risks of transmitting rabies virus from captive domiciliary common marmoset (Callithrix jacchus) to human beings, in the metropolitan region of Fortaleza, state of Ceará, Brazil

INTRODUÇÃO: Uma variante do vírus da raivafoi identificadaem associação a casos de raiva humanos, no Estado do Ceará, transmitidos por saguis (Callithrix jacchus), primatas frequentemente criados como animais de estimação. Essa variante não apresenta proximidade antigênica ou relação genética com as variantes do vírus encontradas em morcegos e mamíferos terrestres das Américas. O objetivo do estudo foi avaliar os fatores de risco de transmissão do vírus da raiva oriundo de sagui (C. jacchus), criado como animal de estimação, para o homem na região metropolitana de Fortaleza, Ceará. MÉTODOS: Foi aplicado um questionário estruturado aos criadores de saguis, residentes nos municípios de Aquiraz e Maranguape, Ceará, enfocando o manejo e a interação desses primatas com humanos. Para avaliação da ocorrência de antígenos rábicos, através do teste de imunofluorescência direta (IFD), foram coletadas amostras de saliva dos saguis domiciliados e semidomiciliados. Com base nos resultados obtidos desses espécimes, foram analisadas amostras de sistema nervoso central (SNC). RESULTADOS: Na análise dos questionários, observou-se a proximidade dos criadores de saguis durante o manejo desses animais nos domicílios, bem como, seus conhecimentos limitados sobre a raiva, demonstrando haver risco quanto à transmissão do vírus. De 29 amostras de saliva de saguis reavaliadas, uma (3,4 por cento) apresentou reação de IFD positiva. De 11 amostras de SNC, três (27,3 por cento) apresentaram positividade. CONCLUSÕES: Os dados laboratoriais estão de acordo com os achados dos questionários, confirmando haver risco da transmissão do vírus da raiva devido à convivência de humanos com saguis (C. jacchus).

INTRODUCTION: In the State of Ceará, a new variant of the rabies virus was identified associated with cases of human rabies transmitted by common marmosets (Callithrix jacchus), which are frequently kept as pets. This new variant does not present antigenic proximity or genetic relationship to variants of the virus isolated from bats and terrestrial mammals from the American continent. The present study aimed to evaluate the risk factors of rabies virus transmission from common marmosets (C. jacchus) maintained as pets in the metropolitan region of Fortaleza, State of Ceará, Brazil, to human beings. METHODS: A questionnaire focusing on animal management and interaction between humans and primates was applied to individuals who had marmosets in the municipalities of Aquiraz and Maranguape. In order to evaluate the presence of rabies antigens by direct immunofluorescence test (DIF), samples of saliva were collected from domiciliary captive marmosets. Based on the detection of rabies antigens, biopsy samples of central nervous system (CNS) were analyzed. RESULTS: Analysis of questionnaire data verified that a close relation exists between humans and their pet marmosets, especially during management practices. Additionally, these people showed minimal knowledge regarding rabies, which represents a greater risk of infection. Of the 29 saliva samples evaluated, one (3.4 percent) was positive for DIF reaction and of the 11 CNS samples, three (27.3 percent) were positive. CONCLUSIONS: Laboratory data are in agreement with the questionnaire findings, which confirm an increased risk of rabies virus transmission due to the close relation between humans and marmosets.

Os morcegos e a raiva na região oeste do Estado de São Paulo / The bats and rabies in the Western region of the State of São Paulo, Brazil

INTRODUÇÃO: O laboratório do Pólo da Alta Sorocabana de Presidente Prudente, SP, em parceria com outras instituições de pesquisa, realizou estudos pertinentes aos morcegos da região oeste do Estado de São Paulo, Brasil. Para tal, foram pesquisadas algumas situações, tais como: a) isolamento do vírus rábico, no período 2006 a 2008; b) as respectivas variantes antigênicas; c) abrigos diurnos do morcego hematófago Desmodus rotundus. MÉTODOS: As amostras para exame foram provenientes de morcegos não hematófagos encaminhadas ao laboratório sendo submetidas aos testes de imunofluorescência direta e prova biológica. As amostras positivas foram caracterizadas antigenicamente por meio do teste de anticorpos monoclonais. Quanto aos morcegos, foram identificados e classificados, e também foi realizado mapeamento de abrigos dos mesmos. RESULTADOS: O laboratório recebeu 1.113 morcegos não hematófagos para diagnóstico laboratorial, sendo 11 (1 por cento) deles positivos, e dentre as amostras positivas, 5 (45,5 por cento) delas tiveram variante antigênica 3 associada ao morcego D. rotundus e 4 (36,5 por cento) foram compatíveis com amostras de morcegos insetívoros. Foram pesquisados 16 abrigos de morcegos hematófagos e observou-se a presença de outras 3 espécies de morcegos não hematófagos convivendo com eles. CONCLUSÕES: Os experimentos mostraram que o vírus rábico continua circulando na região com pelo menos 3 variantes antigênicas, e que, a coabitação de morcegos hematófagos com não hematófagos pode ter alguma relação com a disseminação do vírus rábico.

INTRODUCTION: The Polo da Alta Sorocabana Laboratory in Presidente Prudente, SP, in partnership with other research institutions, conducted studies related to bats from the western region of the State of Sao Paulo, Brazil. Thus, certain situations were investigated, including: a) isolation of the rabies virus from 2006 to 2008; b) identification of respective antigenic variants; and c) characterization of daytime shelters of Desmodus rotundus vampire bats. METHODS: Samples for examination originated from nonhematophagous bats forwarded to the laboratory and subjected to direct fluorescent antibody test and mouse inoculation test. Positive samples were characterized by the monoclonal antibody test. Regarding the bats, they were identified and classified and mapping of their shelters was also performed. RESULTS: The laboratory received 1,113 nonhematophagous bats for rabies diagnosis, 11 (1 percent) of which were positives, and among the positive samples, 5 (45.5 percent) presented antigenic variant 3 (from the bat Desmodus rotundus) and 4 (36.5 percent) were compatible with samples derived from Brazilian insectivorous bats. Sixteen vampire bat shelters were investigated and observation confirmed the presence of another 3 species of nonhematophagous bats coexisting with them. CONCLUSIONS: The experiments showed that at least 3 antigenic variants of rabies virus are circulating in the region and that the cohabitation of vampire bats with nonhematophagous bats could be related to the dissemination of the rabies virus.

Rabies diagnosis and serology in bats from the State of São Paulo, Brazil / Diagnóstico e sorologia de raiva em morcegos do Estado de São Paulo, Brasil

INTRODUCTION: Bats are one of the most important reservoirs and vectors of the rabies virus in the world. METHODS: From 1988 to 2003, the Zoonosis Control Center in São Paulo City performed rabies diagnosis on 5,670 bats by direct immunofluorescent test and mouse inoculation test. Blood samples were collected from 1,618 bats and the sera were analyzed using the rapid fluorescent focus inhibition test to confirm rabies antibodies. RESULTS: Forty-four (0.8 percent) bats were positive for rabies. The prevalence of rabies antibodies was 5.9 percent using 0.5IU/ml as a cutoff. Insectivorous bats (69.8 percent) and bats of the species Molossus molossus (51.8 percent) constituted the majority of the sample; however, the highest prevalence of antibodies were observed in Glossophaga soricina (14/133), Histiotus velatus (16/60), Desmodus rotundus (8/66), Artibeus lituratus (5/54), Nyctinomops macrotis (3/23), Tadarida brasiliensis (3/48), Carollia perspicillata (3/9), Eumops auripendulus (2/30), Nyctinomops laticaudatus (2/16), Sturnira lilium (2/17) and Eumops perotis (1/13). The prevalence of rabies antibodies was analyzed by species, food preference and sex. CONCLUSIONS: The expressive levels of antibodies associated with the low virus positivity verified in these bats indicate that rabies virus circulates actively among them.

INTRODUÇÃO: Morcegos são um dos mais importantes reservatórios e vetores do vírus da raiva no mundo. MÉTODOS: No período entre 1998 e 2003, o Centro de Controle de Zoonoses da Cidade de São Paulo realizou o diagnóstico de raiva em 5.670 morcegos utilizando as técnicas de imunofluorescência direta e inoculação intracerebral em camundongos. Sangue foi coletado de 1.618 espécimes para pesquisa de anticorpos pela técnica de inibição de foco de fluorescência rápida. RESULTADOS: Quarenta e quatro (0,8 por cento) morcegos foram positivos para raiva. A prevalência de anticorpos foi de 5,9 por cento usando 0,5UI/ml como ponto de corte. Os morcegos de hábito alimentar insetívoro (69,8 por cento) e os morcegos da espécie Molossus molossus (51,8 por cento) representaram a maioria da amostra. Entretanto, as mais altas prevalências de anticorpos foram observadas nos morcegos Glossophaga soricina (14/133), Histiotus velatus (16/60), Desmodus rotundus (8/66), Artibeus lituratus (5/54), Nyctinomops macrotis (3/23), Tadarida brasiliensis (3/48), Carollia perspicillata (3/9), Eumops auripendulus (2/30), Nyctinomops laticaudatus (2/16), Sturnira lilium (2/17) e Eumops perotis (1/13). A prevalência de anticorpos foi analisada por espécie, hábito alimentar e sexo. CONCLUSÕES: O expressivo nível de anticorpos associado à baixa positividade para o vírus da raiva entre os morcegos estudados indica que o vírus circula ativamente entre morcegos.

Is the skin sensitivity test required for administering equine rabies immunoglobulin.

Background. Rabies immunoglobulins are life-saving in patients with severe exposure to rabies. Despite the high degree of purification of equine rabies immunoglobulin (ERIG), the product inserts still recommend a skin sensitivity test before administration of this heterologous serum. A recent WHO recommendation states that there are no scientific grounds for performing a skin test before administering ERIG because testing does not predict reactions and it should be given irrespective of the result of the test. In this conflicting situation, we assessed the use of the skin sensitivity test in predicting adverse events to ERIG. Methods. The data analysed were from the Antirabies Clinic of the Kempegowda Institute of Medical Sciences Hospital, Bengaluru, India. The period of study was 26 months (June 2008–July 2010). The skin sensitivity test was validated by evaluating its sensitivity, specificity, predictability, falsepositive and false-negative results. Results. A total of 51 (2.6%) adverse events were reported in 31 (1.5%) subjects. Most of these were mild to moderate in nature and subsided without medication. There was no serious adverse event. The sensitivity and specificity of the skin sensitivity test to predict an adverse event was 41.9% and 73.9%, respectively. Conclusion. Our experience with the skin sensitivity test suggests that it may not be required before administering ERIGs, as recommended by WHO.

Antemortem diagnosis of human rabies in a veterinarian infected when handling a herbivore in Minas Gerais, Brazil / Diagnóstico ante-mortem de raiva humana em médico veterinário infectado por manipulação de herbívoro, Minas Gerais, Brasil

The Ministry of Health's National Human Rabies Control Program advocates pre-exposure prophylaxis (PEP) for professionals involved with animals that are at risk of contracting rabies. We report an antemortem and postmortem diagnosis of rabies in a veterinarian who became infected when handling herbivores with rabies. The antemortem diagnosis was carried out with a saliva sample and a biopsy of hair follicles using molecular biology techniques, while the postmortem diagnosis used a brain sample and conventional techniques. The veterinarian had collected samples to diagnose rabies in suspect herbivores (bovines and caprines) that were subsequently confirmed to be positive in laboratory tests. After onset of classic rabies symptoms, saliva and hair follicles were collected and used for antemortem diagnostic tests and found to be positive by RT-PCR. Genetic sequencing showed that the infection was caused by variant 3 (Desmodus rotundus), a finding confirmed by tests on the brain sample. It is essential that professionals who are at risk of infection by the rabies virus undergo pre-exposure prophylaxis. This study also confirms that molecular biology techniques were used successfully for antemortem diagnosis and therefore not only allow therapeutic methods to be developed, but also enable the source of infection in human rabies cases to be identified accurately and quickly.

O Programa Nacional de Controle da Raiva Humana do Ministério da Saúde preconiza o esquema profilático pré-exposição (PEP) para profissionais envolvidos com animais expostos ao risco de contraírem raiva. O presente trabalho relata o diagnóstico de raiva (ante e post-mortem) em veterinário infectado por manipulação de herbívoros raivosos. O diagnóstico laboratorial ante-mortem foi efetuado a partir da saliva e biópsia de folículo piloso, utilizando técnicas de biologia molecular e o post-mortem a partir do tecido cerebral e de técnicas convencionais. O médico veterinário coletou amostras para diagnóstico de raiva em herbívoros (bovinos e caprinos) suspeitos que, posteriormente, foram confirmados positivos em laboratório. Após a apresentação dos sintomas clássicos de raiva e realizadas as provas de diagnóstico ante-mortem com saliva e folículo piloso, ambas as amostras apresentaram resultados positivos pelo nested-RT-PCR. O sequenciamento genético revelou que a infecção se deu pela variante 3 do Desmodus rotundus, resultados estes confirmados com a amostra do cérebro. É indispensável que profissionais expostos ao risco de infecção pelo vírus da raiva realizem a profilaxia pré-exposição. Ressalta-se, também, que as técnicas de biologia molecular apresentaram bons resultados para a realização de diagnóstico ante-mortem, propiciando o desenvolvimento de métodos terapêuticos, e determinando com precisão e rapidez a fonte de infecção dos casos de raiva humana.

Pathogenicity of different rabies virus isolates and protection test in vaccinated mice / Patogenicidade de diferentes isolados do vírus da raiva e teste de proteção em camundongos vacinados

This study was aimed to evaluate and compare the pathogenicity of rabies virus isolated from bats and dogs, and to verify the efficacy of a commercial rabies vaccine against these isolates. For evaluation of pathogenicity, mice were inoculated by the intramuscular route (IM) with 500MICLD50/0.03mL of the viruses. The cross-protection test was performed by vaccinating groups of mice by the subcutaneous route and challenged through the intracerebral (IC) route. Isolates were fully pathogenic when inoculated by the IC route. When inoculated intramuscularly, the pathogenicity observed showed different death rates: 60.0 percent for the Desmodus rotundus isolate; 50.0 percent for dog and Nyctinomops laticaudatus isolates; 40.0 percent for Artibeus lituratus isolate; 9.5 percent Molossus molossus isolate; and 5.2 percent for the Eptesicus furinalis isolate. Mice receiving two doses of the vaccine and challenged by the IC route with the isolates were fully protected. Mice receiving only one dose of vaccine were partially protected against the dog isolate. The isolates from bats were pathogenic by the IC route in mice. However, when inoculated through the intramuscular route, the same isolates were found with different degrees of pathogenicity. The results of this work suggest that a commercial vaccine protects mice from infection with bat rabies virus isolates, in addition to a canine rabies virus isolate.

O estudo avaliou e comparou as propriedades patogênicas de cinco isolados do vírus da raiva de morcegos e um isolado do vírus da raiva de cão e analisou a eficácia de vacina comercial contra estes isolados, em camundongos. Para o estudo de patogenicidade camundongos foram inoculados pela via IM com 0,1 mL contendo 500MICLD50/0,03mL das amostras de vírus. Quando inoculados pela via IC, os isolados do vírus da raiva provocaram a morte de 100 por cento dos camundongos. No entanto, 500MICLD50/0,03mL das mesmas amostras, inoculadas pela via IM, ocasionaram mortalidade de: 60,0 por cento quando a amostra era de Desmodus rotundus; 50,0 por cento de cão e de Nyctinomops laticaudatus; 40,0 por cento de Artibeus lituratus; 9,5 por cento de Molossus molossus; e 5,2 por cento de Eptesicus furinalis. Camundongos que receberam duas doses de vacina foram protegidos quando desafiados pela via IC, com todas as amostras testadas. Quando os camundongos receberam uma dose da mesma vacina, houve proteção parcial daqueles desafiados com a amostra de cão. Todos os isolados do vírus da raiva testados foram patogênicos para camundongos, inoculados pela IC. No entanto, pela via IM, os mesmos isolados mostraram diferentes graus de patogenicidade. Concluiu-se também que a vacina comercial contra raiva protegeu os camundongos desafiados com amostras de vírus isolados de morcegos e de cão.

Estudo imunológico e genético de 10 isolados do vírus da raiva de morcegos do Rio de Janeiro, Sudeste do Brasil / Immunological and genetic study of 10 bat rabies virus isolates from Rio de Janeiro State, Southeast

O presente trabalho visou estudar 10 isolados de vírus da raiva de morcegos hematófagos e não-hematófagos do Estado do Rio de Janeiro em suas características genéticas quanto aos genes N e G, além da resposta de camundongos vacinados com a vacina anti-rábica produzida pela replicação da amostra Pitman-Moore em cultivo celular, frente ao desafio com estes isolados virais, utilizando-se um ensaio imunológico baseado no teste de potência NIH. A vacina anti-rábica utilizada na imunização dos camundongos ofereceu proteção em mais de 80% dos camundongos vacinados com a diluição 1:5 da vacina, frente à maioria dos isolados. A análise filogenética do gene da proteína N apresentou um padrão de agregação dividido em variante de morcego hematófago e variante de morcego insetívoro, com todos os isolados de morcegos frugívoros Artibeus sp. tendo sido segregados com a variante característica de morcegos Desmodus rotundus. Foram observadas diferenças filogenéticas entre as variantes do vírus da raiva de morcego hematófago isoladas na Região Noroeste do Estado do Rio de Janeiro e aquelas isoladas nas Regiões Metropolitana e Sul do Estado. A substituição do resíduo ácido aspártico por ácido glutâmico na posição 118, encontradas na caracterização genética da proteína G dos isolados 704/97BR-DR e 151/98BR-DR, permite inferir que esta posição esteja relacionada à antigenicidade viral. Não foram observadas diferenças genéticas temporais entre os isolados estudados. A vacina anti-rábica utilizada ofereceu proteção satisfatória contra a maioria dos isolados estudados.

In the present study we analyzed 10 bats rabies viruses isolated from Rio de Janeiro State, focusing on its genetic characteristics from genes N and G, and also in the response of mice vaccinated with cell-culture rabies vaccine, produced with the Pitman-Moore strain, after viral challenge with bat rabies isolates, using an immunologic essay based on NIH vaccine potency test. The vaccine used conferred protection in more than 80% of the mice vaccinated with 1:15 vaccine dilution, after viral challenge. N gene genetic analysis divided the rabies virus isolates into haematophagous and insectivorous bat variants, with all isolates from Artibeus sp. frugivorous bats being clustered with the variant characteristic of the Desmodus rotundus vampire bat. Phylogenetic differences between isolates from Northeast Region and those from the Metropolitan and South Regions of Rio de Janeiro State were observed. The substitution of an aspartic acid to a glutamic acid found in the position 118 of G gene genetic characterization from samples 704/97BR-DR and 151/98BR-DR seems to be related to viral antigenicity. There were no time-related genetic differences between the studied samples. The vaccine employed was found with satisfactory protection against the majority of the isolates used.

Diagnóstico de un caso de rabia humana en Jujuy, 2008 / Diagnosis of a human rabies case in Jujuy, 2008

El 22 de Julio de 2008, un niño de 8 años de edad, residente en la provincia de Jujuy, Argentina, falleció por una encefalitis producida por el virus de la rabia. El diagnóstico se realizó mediante la detección de anticuerpos en suero y se confirmó por inmunofluorescencia en el cerebro. La tipificación antigénica correspondió a la variante 1 trasmitida por perros. El análisis molecular estableció que el virus detectado es de la misma variante genética que circula en Jujuy desde 2003. Este trabajo resume la evolución clínica del paciente y la posterior investigación epidemiológica que reveló el antecedente de mordedura por un perro 60 días antes de la iniciación de la enfermedad y la ausencia de un tratamiento antirrábico post-exposición.

On July 22, 2008, a previously healthy 8 years old boy from Jujuy, Argentina, died of encephalitis later confirmed as rabies. Diagnosis was made on the basis rabies-specific antibodies presence in a serum sample and it was confirmed by detection of the viral antigens in brain necropsy using the inmunofluorescent test. Antigenic characterization identified dog as source of infection. Molecular analysis recognized the same genetic variant circulating in Jujuy since 2003. This report presents the patient's clinical course and the epidemiologic investigation that revealed a dog bite 60 days before the illness onset and the lack of rabies treatment.