Cattle rabies: the effect of clinical evolution, viral genetic lineage, and viral load on the severity of histological lesions / Raiva bovina: relação do curso clínico, da linhagem genética do vírus e carga viral com a intensidade de lesões histológicas

Our objective was the characterization and staging of histological lesions in different anatomical sites of the central nervous system (CNS) of rabid cattle. The severity of the lesions was compared with the clinical stages of the disease, the variants of viral isolates, and with the load of virus. Thirty-one spontaneously affected rabid cattle the state of Santa Catarina underwent clinical follow-up and were eventually necropsied. CNS tissues were sampled and submitted to direct fluorescent antibody technique (DFAT), immunohistochemistry (IHC), routine histopathology with hematoxylin and eosin stain (HE), reverse transcriptase polymerase chain reaction (RT-PCR), and polymerase chain reaction in quantitative reverse transcriptase in real time (qRT-PCR). Affected cattle were allotted in four groups according to their clinical stage when euthanized: G1, euthanized while standing; G2, euthanized when in sternal recumbence; G3, euthanized when in lateral recumbence; and G4, affected cattle with natural death. In order to evaluate the degree of severity of the lesions and the presence of Negri bodies (NBs), the brain was sectioned at 9 sites. Additionally, spinal cord and trigeminal ganglion sections were examined. The intensity of the lesions was graded as either absent, mild, moderate, or marked, and the presence or absence of the NBs was noted. Histological lesions were characterized by lymphocytic and monocytic meningoencephalitis with NBs in 28 cases. In all analyzed groups, intensities of histological lesions ranging from mild to severe were observed. Brain regions with the highest inflammatory lesion intensity were the medulla at the level of obex, followed by the colliculus and thalamus. NBs were observed in a higher percentage in the cerebellum, followed by medulla at the obex level, striatum complex, and frontal telencephalon. The duration of the clinical course of the disease did not influence the intensity of the inflammatory lesion, but it did influence the presence of NBs, with a higher percentage of these inclusions in cattle that died naturally than in euthanized cattle. All isolated rhabdovirus included in this study were genetically compatible with samples from hematophagous bats Desmodus rotundus. The evaluation by qRT-PCR did not demonstrate a correlation between lesion intensity and the amount of virus.(AU)

Nosso objetivo foi a caracterização e estadiamento de lesões histológicas em diferentes locais anatômicos do sistema nervoso central (SNC) de bovinos raivosos. A gravidade das lesões foi comparada com os estágios clínicos da doença, as variantes dos isolados virais e com a quantidade de vírus. Trinta e um bovinos do estado de Santa Catarina, afetados naturalmente por raiva, foram acompanhados clinicalmente e, ao final, necropsiados. Os tecidos do SNC foram amostrados e submetidos a imunofluorescência direta, imunohistoquímica, histopatologia de rotina, reação em cadeia da polimerase via transcriptase reversa (RT-PCR) e reação em cadeia da polimerase em transcriptase reversa quantitativa em tempo real (qRT-PCR). Os bovinos afetados foram distribuídos em quatro grupos, de acordo com sua fase clínica: G1, eutanasiados quando ainda se mantinham em pé; G2, eutanasiados quando em decúbito esternal; G3, eutanasiados quando em decúbito lateral; e G4, bovinos afetados com morte natural. Para avaliar o grau de gravidade das lesões e a presença de corpúsculos de Negri (CNs), o cérebro foi seccionado em 9 locais. Além disso, seções da medula espinhal e do gânglio trigêmeo foram examinadas. A intensidade das lesões foi graduada como ausente, leve, moderada ou acentuada, e a presença ou ausência dos CNs foi anotada. Lesões histológicas foram caracterizadas por meningoencefalite linfocítica e monocítica com CNs em 28 casos. Em todos os grupos analisados foram observadas intensidades de lesões histológicas variando de leve a grave. As regiões cerebrais com maior intensidade de lesão inflamatória foram o bulbo no nível do obex, seguido do colículo e tálamo. CNs foram mais prevalentes no cerebelo, seguido pelo bulbo ao nível do óbex, corpo estriado e telencéfalo frontal. A duração do curso clínico da raiva não influenciou a intensidade da lesão inflamatória, mas influenciou a presença de CNs, com maior porcentagem dessas inclusões em bovinos que morreram naturalmente do que em bovinos sacrificados. Todos os isolados rabdovírus obtidos neste estudo eram geneticamente compatíveis com amostras provenientes de morcegos hematófagos Desmodus rotundus.(AU)

Vigilancia, prevención y control de la rabia: Ciudad de Buenos Aires: Junio 2018 / Surveillance, prevention and control of rabies: City of Buenos Aires: June 2018

La rabia es una enfermedad viral, de distribución mundial que afecta al hombre y a todos los mamíferos tanto domésticos como silvestres, con una letalidad del 100% afectando el sistema nervioso central. Se transmite por medio de la inoculación del virus contenido en la saliva del animal infectado, principalmente por mordeduras o el lamido de heridas, o por predación cuando un animal caza un murciélago infectado y toma contacto con el virus desde el encéfalo del quiróptero. Otras formas de transmisión, menos frecuentes son por trasplante de tejidos infectados o por aerosoles. En este apartado, se describe la situación epidemiológica de esta zoonosis en la Ciudad de Buenos Aires: observación de animales mordedores, detección de virus rábico en muestras mediante diagnóstico de laboratorio, vacunación de animales y control poblacional mediante esterilizaciones quirúrgicas, acciones de control de focos de rabia, y seguimiento de animales con exposición a murciélagos positivos a rabia o no analizables

Kinetics of rabies antibodies as a strategy for canine active immunization

Rabies, a zoonosis found throughout the globe, is caused by a virus of the Lyssavirus genus. The disease is transmitted to humans through the inoculation of the virus present in the saliva of infected mammals. Since its prognosis is usually fatal for humans, nationwide public campaigns to vaccinate dogs and cats against rabies aim to break the epidemiological link between the virus and its reservoirs in Brazil. During 12 months we evaluated the active immunity of dogs first vaccinated (booster shot at 30 days after first vaccination) against rabies using the Fuenzalida-Palácios modified vaccine in the urban area of Botucatu city, São Pauto state, Brazil. Of the analyzed dogs, 54.7% maintained protective titers (≥0.5 IU/mL) for 360 days after the first vaccination whereas 51.5% during all the study period. The present results suggest a new vaccination schedule for dogs that have never been vaccinated. In addition to the first dose of vaccine, two others are recommended: the second at 30 days after the first and the third dose at 180 days after the first for the maintenance of protective titers during 12 months.

Molecular epidemiology of rabies virus isolated of herbivores from Brazilian Amazon / Epidemiologia molecular de vírus da raiva isolados de herbívoros procedentes da Amazônia brasileira

Rabies virus samples (n = 17) A1 to A3 exhibit a similar composition and geographic distribution. Diverse composition of remaining groups of N and G gene is attributable to different sequences used in the alignments for each genomic region. Glycoprotein amino acid sequence showed molecular markers in sub-lineages A2, A3, A4 and A7. This information provides a better comprehension of molecular epidemiology of rabies, starting with the knowledge of viral lineages circulating in the Brazilian Amazon.

Amostras do vírus da raiva (n = 17) isoladas de bovinos (n = 11), equinos (n = 4) e bubalinos (n = 2) procedentes do Pará (n = 7), Tocantins (n = 6) e Rondônia (n = 4) foram submetidas à técnica de RT-PCR para amplificação parcial dos genes da Nucleoproteína (N) e Glicoproteína (G). As sequências nucleotídicas obtidas foram analisadas pelo método de reconstrução filogenética Neighbor-Joining com o modelo evolutivo Kimura 2-parâmetros. Todas as 17 amostras pertenceram ao cluster A, que se encontrou na linhagem associado com morcego hematófago Desmodus rotundus. A análise filogenética baseada nos genes N e G, sugere a presença de cinco sublinhagens (A1-A5) e sete sublinhagens (A1-A7), respectivamente. Quando se compara ambas as filogenias, as sublinhagens A1 até A3 mostram composição e distribuição geográfica concordante, já a diversidade observada na composição das sublinhagens restantes é atribuída ao uso de sequências de diferentes alinhamentos. A glicoproteína mostrou marcadores moleculares nas sublinhagens A2, A3, A4 e A7, o que fornece elementos para melhor compreensão da epidemiologia molecular da raiva das linhagens circulantes na Amazônia Brasileira.

Comportamiento y distribución espacial del virus rábico en la provincia La Habana, Cuba, 1998-2010 / Behavior and spatial distribution of rabic virus in Havana province, Cuba, 1998-2010

Objetivo: Analizar el comportamiento y distribución espacial de los focos rábicos en la provincia La Habana, de 1998 hasta 2010. Métodos: Se realizó un estudio observacional descriptivo retrospectivo de los casos de especie animal positivos a rabia, examinados en el Departamento de Rabia del Laboratorio Provincial de forma pasiva, de 1998 hasta 2010. Se incluyó 1 196 muestras de cerebros de carnívoros, quirópteros y herbívoros estudiados en la provincia. Se empleó la técnica de inmunofluorescencia directa para el diagnóstico de rabia. La descripción de la distribución espacial se realizó a partir de los sistemas de información geográficos digitalizados. Resultados: Los municipios periféricos tienen mayor índice de casos positivos a rabia en mangostas (mal llamado hurón en Cuba), perros y gatos; con 85 casos positivos de un total 1 196 muestras (7,11%) en un periodo de 13 años. Conclusiones: La utilización de mapas nos brinda gran utilidad ubicando geográficamente los focos rábicos. El mayor reporte de casos se notificó en cuatro municipios periféricos (Boyeros, Arroyo Naranjo, Cotorro y Guanabacoa), ubicados geográficamente en el centro y sur de la provincia La Habana.

Objective: To analyze the behavior and spatial distribution of rabies foci in the province of Havana, 1998-2010. Methods: We conducted a retrospective observational study of cases of animal species positive for rabies, examined passively in the Department of Rabies of the Provincial Laboratory, from 1998-2010. 1196 brain samples of carnivores and herbivores bats studied in the province were included. We used the direct immunofluorescence technique for the diagnosis of rabies. The description of the spatial distribution was made from the digitized geographical information systems. Results: The peripheral municipalities have larger number of cases positive for rabies in mongooses (so-called ferret in Cuba), dogs and cats, with 85 positive cases out of a total 1196 samples (7.11%) over a period of 13 years. Conclusions: The use of maps is useful in the geographic location of rabies foci. The greater reporting of cases occurred in four peripheral municipalities (Boyeros, Arroyo Naranjo, Cotorro and Guanabacoa), geographically located in the center and south of the province of Havana.

Humoral immune response in dogs and cats vaccinated against rabies in southeastern Brazil

Brazil holds annual nationwide public campaigns to vaccinate dogs and cats against rabies. The presence of rabies antibodies in these animals, which are among the main transmitters of rabies to humans, is a good indicator that they are immunized and protected.Methods In the present study we analyzed 834 serum samples from dogs and cats from the Southeast of Brazil (Presidente Prudente and Dracena cities), 12 months after the 2009 vaccination campaign. We used the technique known as rapid fluorescent focus inhibition test (RFFIT) and considered reactant those sera with values higher 0.5 IU/mL. Results and discussion Reactant sample results in Presidente Prudente were 153 (51.0%) for dogs and 59 (32.6%) for cats, and in Dracena 110 (52.1%) for dogs and 71 (50.0%) for cats. We discussed vaccine coverage of animals involved in this experiment, and observed low titers < 0.5 IU/mL, especially in cats from Presidente Prudente.Conclusion According to the results presented in our experiment, we suggest that titers below 0.5 IU/mL are worrisome and that, for multiple reasons, animals should be immunized against rabies in the period between public vaccination campaigns. Hence, the desired vaccine coverage was not accomplished, especially among cats from Presidente Prudente.

Raiva humana / Human rabies

JUSTIFICATIVA E OBJETIVOS: A raiva humana é extremamente relevante do ponto de vista clínico e de saúde pública, por se tratar de moléstia fatal em aproximadamente 100,0% dos casos, embora haja relatos de cura após a instalação dos sinais e sintomas, um dos quais no Brasil, em 2008. O objetivo do presente estudo foi apresentar uma atualização sobre a raiva humana em seus aspectos epidemiológicos, clínicos e terapêuticos, destacando o Protocolo Recife, a fim de subsidiar médicos generalistas com informações úteis ao atendimento clínico de qualidade. CONTEÚDO: Após um período variável de incubação, iniciam-se os pródromos da doença (manifestações inespecíficas). A progressão da enfermidade é acompanhada de grave ansiedade, excitação e agitação psicomotora, evoluindo para manifestações relacionadas à disfunção do tronco cerebral. O tratamento é usualmente baseado nas medidas de apoio das complicações da infecção. CONCLUSÃO: A raiva humana permanece como significativo problema de saúde no Brasil, principalmente por ser uma doença - do ponto de vista clínico, diagnóstico e profilático - ainda pouco conhecida pelos médicos generalistas. Dessa forma, ações de educação continuada constituem um importante elemento para abordagem correta dos pacientes sob o risco de desenvolver a enfermidade.

BACKGROUND AND OBJECTIVES: The human rabies is extremely important for the internal medicine and public health, becauseis a fatal disease in nearly 100% of cases, although there are some reports of healing after the installation of signs and symptoms, one of which in Brazil in 2008, resulting Recife Protocol for treatmentof disease. The aim of this study is to present an update on the human rabies in their epidemiological, clinical and therapeutic aspects, highlighting the Recife Protocol, in order to subsidize generalpractitioners with useful information for clinical care quality. CONTENTS: After a variable period of incubation, begins the prodroms disease (nonspecific). The disease progression is accompanied by severe anxiety, arousal, and psychomotor agitation, progressing to complications due to dysfunction of the brainstem. The treatment is usually based on measures of support from complications of the infection. CONCLUSION: Human rabies remains a significant health problem in Brazil, mainly because it is a disease - the clinicalpoint of view, diagnosis and prophylaxis - that still not wellknown by general practitioners. Thus, actions of continuing education are an important element to appropriate approach for the individuals at risk of developing the disease.

Fatal rabies despite post-exposure prophylaxis.

Only sporadic reports of failure of post-exposure prophylaxis for rabies exist in the published literature. We are reporting such a case in a 3-year-old boy. The child had Category III dog bite on his right thigh. He presented with progressive ascending paralysis, finally developing quadriplegia and respiratory paralysis. Typical hydrophobia and aerophobia were absent. He received four doses of antirabies cell culture vaccine. He did not receive antirabies immunoglobulin. The boy succumbed on the 23 rd day of the dog bite. Diagnosis of rabies was confirmed in the laboratory by demonstration of Negri bodies, direct fluorescent antibody test and reverse transcriptase-polymerase chain reaction either on impression smear of brain or a piece of brain taken during autopsy.

Levantamento e identificação dos aspectos epidemiológicos da raiva canina no município de Cuiabá – MT / Survey and identification of the epidemiological aspects of canine rabies in the city of Cuiabá-MT

Reconhecida desde a antiguidade, a raiva é uma infecção aguda do sistema nervoso central que acomete mamíferos, sendo causada por um RNA vírus da família Rabidoviridae, gênero Lyssavírus. O Brasil, desde a implantação do programa de controle da raiva em áreas urbanas, vem apresentando um declínio de casos de raiva em cães e em seres humanos. Em Cuiabá, as atividades realizadas pelo Centro de Controle de Zoonoses voltadas para o controle da raiva como: vacinação antirrábica animal, bloqueios de foco, captura de animais errantes, entre outros, permitiu o bloqueio da circulação do vírus na espécie canina. Desde 2008, o município de Cuiabá não registra nenhum caso da doença na espécie canina. Com o objetivo de conhecer a distribuição temporal da raiva canina em Cuiabá- MT, assim como identificar os aspectos epidemiológicos dos cães infectados pelo vírus rábico e verificar as medidas de profilaxia para a raiva canina, adotadas pelo Centro de Controle de Zoonose do município de Cuiabá no período de janeiro de 2002 a dezembro de 2008, realizou-se o presente estudo. Para o estudo observacional descritivo foi empregado o banco de dados referente à série histórica do CCZ e do Laboratório de Apoio a Saúde Animal – LASA ambos situados no município de Cuiabá- MT. O período de estudo foi de janeiro de 2002 a dezembro de 2008. Neste período foram examinadas 1021 amostras de cérebro de cães, destas 8,71% (89/1021) foram positivas e 91,29% (932/1021) negativas para a raiva. Os meses de maior incidência da doença foram os meses de janeiro 15,05% (14/93), fevereiro 12,5% (9/72), março 12,5% (9/72), abril 14,14% (9/72) e dezembro 13,69% (10/73). O maior número de cães doentes era macho 59,55% (53/89) com idade acima de dois anos 50,55% (45/89) e não domiciliados 67,41% (60/89). Em relação à imunoprofilaxia, a maioria dos cães 99,63% foi vacinada em campanhas. A cobertura vacinal ficou acima dos 80% exceto em 2006. Entre os animais que apresentaram a enfermidade o maior número, 67,41% (60/89), foi de cães não domiciliados, os chamados cães errantes. O percentual de cães domiciliados infectados pelos VR foi igual a 32,58% (29/89). As campanhas de vacinação, portanto, são fundamentais para a imunização do maior número de animais possível e a sociedade deve se conscientizar sobre a importância da raiva e as medidas que devem ser tomadas para controlá-la.

Known since the ancient times, the rabies is an acute infection of the central nervous system that affects mammals, caused by an RNA virus of the Rhabidoviridae family, Lyssavirus gender. Since the implantation of the urban area rabies control program in Brazil the number of cases in dogs and human have shown a decrease. In Cuiabá, the efforts to control the rabies, such as animal vaccination, focus isolation, capture of nomad animals and others realized by the Zoonosis Control Center has leaded to locking in the viral circulation in the canine species. Since 2008, zero cases of the disease in dogs were reported. In order to know the temporal distribution of canine rabies in Cuiabá – MT and identify the epidemiologic aspects of the rabies’s infected dogs, and verify the canine rabies’s profilatic actions of the Zoonosis Control Center of the city of Cuiabá, during the period of January, 2002 to December , 2008, the present study was performed. The historic data base from Cuiabá - MT was obtained at the Zoonosis Control Center and at the Animal Health Support Laboratory and used to perform the descriptive and observational study. During the performance of the study, 1021 samples of canine’s brains were examined, 8,71% (89/1021) of them were positive and 91,29% (932/1021) of them were negative for the rabies test. The Months with higher incidence were January with 15,05% (14/93), February with 12,5% (9/72), March with 12,5% (9/72), April with 14,14% (9/72) and December with 13,69% (10/73). The major part of the infected dogs were males with 59,55% (53/89) older than two years old 50,55% (45/89) and were nomads animals 67,41% (60/89). 99,63% of the infected dogs were vaccinated in anti rabies vaccination campaigns. The vaccinal cover was higher than 80%, except in 2006. The percentual of the domiciled infected dogs by the rabies virus were 32,58% (29/89). Therefore the vaccination campaigns are essential for the immunization of a higher number of animals, and the society must be awareabout the importance of rabies and about the actions to control it.

Epizootia da raiva canina no município de Corumbá em 2008: descrição e avaliação dos atendimentos antirrábicos humanos / Epizootic canine rabies in the municipality of Corumbá in 2008: description and evaluation of human care antirrábicos

A raiva é uma enfermidade infecto-contagiosa de caráter zoonótico responsável por milhares de mortes anualmente, de animais em todo o mundo, incluindo seres humanos. A doença é causada por um vírus que afeta predominantemente os mamíferose caracteriza-se por apresentar curso agudo e fatal. Este estudo foi realizado com a finalidade de verificar as condições de profilaxia da raiva humana, em Corumbá, Mato Grosso do Sul, Brasil, com vistas à obtenção de melhor orientação quanto ao uso de vacinas e soros anti-rábicos. Com o fim de se determinar melhores estratégias de profilaxia e controle da enfermidade foram analisadas 1.274 fichas de registros de atendimento contendo dados de pessoas que procuraram atendimento profilático antirrábico humano, no ano de 2008. Os demais dados foram obtidos através do levantamento de prontuários médico-ambulatoriais de pessoas atendidas pela Vigilância Epidemiológica do município de Corumbá, informações disponíveis no Sistema Nacional de Agravos de Ficha de Investigação Atendimento Antirrábico Humano (SINAN) e em informações disponíveis no Centro de Controle de Zoonoses de Corumbá. Os resultados evidenciaram que o grupo etário mais atingido foi o de indivíduos menores de dez anos; que 87,5 por cento dos acidentes foram provocados por animais da espécie canina; 51,8 por cento dos acidentes foram no próprio domicílio; vários casos deixariam de ser tratados, caso houvesse acompanhamento adequado no período de dez dias; As informações obtidas constituem ferramentas importantes para a instituição de programas de prevenção de mordeduras, baseados no perfil não só da vítima, mas também do animal agressor, além de permitirem estabelecer fatores de risco para prevenir a ocorrência de agressões.

Rabies is a zoonotic viral disease which causes thousands of humans and animals deaths worldwide annually. It is a viral disease which affects mainly mammals and has acute and fatal course. This study was carried out to verify the situation of rabies prophylaxisin the State of Mato Grosso do Sul (Brazil), and was made with a view to obtain better guidance on the use of vaccines and anti-rabic serum. A total of 1,274 individual cards were analysed, in wich there was registered information about people who sought medical help at Corumbá city in 2008. The study of this information can provide improved strategies of prevention and control of this disease. The data were obtainedthrough the accompaniment of doctor-ambulatories handbooks of peoples assisted by the epidemic surveillance of Corumbá City, which information are disposable in the Sistema Nacional de Agravos de Ficha de Investigação Atendimento Antirrábico Humano (SINAN) and completed by information of Centre for Zoonosis Control ofCorumbá. The results showed that 87.5% of the accidents were provoked by animals of canine species; people under 10 years old were those most affected; 51,8% of the accidents happened in the home itself; a large number of cases could be eliminated ifthere were more intensive and careful observation over a period of 10 days. The data are important for establishing bite prevention programs based on the profile of both victims and biting animals, besides identifying risk factors for animal bites prevention.

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.

Rabies review: immunopathology, clinical aspects and treatment

Among the diseases of viral origin, rabies is unique in its distribution and range of victims since it can afflict all warm-blooded animals. The interaction between the virus and the host population has facilitated the survival of the disease. The rabies virus (RV) has not changed in any significant way and has been capable of taking advantage of conditions suited to the continuance of rabies. Infection by RV is invariably lethal in the absence of protective immune response which, however, can contribute to the pathogenesis of rabies. Proinflammatory cytokines might affect, directly or indirectly, the levels of neurotrophins, growth factors, neurotransmitters and neurotoxins in the brain by activating glia, neurons, and vascular and immune cells. Although understanding of the bases for neuronal dysfunction and neuronal death during RV infection has progressed, no fundamental abnormality has been identified so far.

Immunopathology of rabies infection in mice selected for high or low acute inflammatory reaction

Rabies is a severe and lethal disease that produces a slight inflammatory response during the infection process. We analyzed the immunopathological mechanisms that occur in the central nervous system (CNS) using mice genetically selected for maximal or minimal acute inflammatory reaction (AIRmax or AIRmin). As viral samples, we adopted the antigenic variant 3 (AgV3) of rabies virus from hematophagous bats and a fixed virus strain (PV1 43/3). Titration of specific antibodies was performed using enzyme-linked immunosorbent assay (ELISA). We observed a slight increase in IgG and IgG1 isotypes in infected AIRmax mice. Incubation period, determined by intracerebral inoculation with 100 LD50, was 6-7 days for PV1 43/4 strain and 9-10 days for AgV3. No difference in viral replication was noticed between AIRmax and AIRmin mice. Mortality was 100 percent with both viral strains. Histopathological analysis of brains and spinal cords showed inflammatory foci in all regions of the CNS. No differences were noticed in the number of neutrophils. Negri bodies were observed in practically all sites analyzed. Results suggested that inflammatory reaction is not a determining factor in the susceptibility to rabies infection.

Renal involvement in human rabies: clinical manifestations and autopsy findings of nine cases from northeast of Brazil

Foi realizado estudo retrospectivo de nove casos de raiva internados em um hospital de Fortaleza, Brasil. Autópsia foi realizada em todos os casos. As idades variaram de 3 a 81 anos. Todos foram agredidos por cães. O tempo entre o acidente e a admissão hospitalar variou de 20 a 120 dias (média de 45 ± 34 dias). O tempo de internamento variou de 1 a 9 dias (média de 5.5 ± 3.1 dias). Os sinais e sintomas observados foram febre, hidrofobia, aerofobia, agitação, desorientação, dispnéia, sialorréia, vômitos, oligúria, faringite, dor e hipoestesia no local da mordida, cefaléia, síncope, tosse, hematêmese, midríase, hematúria, constipação, dor cervical e priapismo. Em três de seis pacientes (50%) foi encontrada evidência de insuficiência renal aguda, definida como creatinina > 1.4 mg/dL. Os achados de autópsia do tecido renal foram congestão glomerular leve a moderada e congestão capilar peritubular leve a intensa. Necrose tubular aguda foi encontrada em dois casos. Estes achados são inespecíficos, de modo que a instabilidade hemodinâmica, causada por disfunção autonômica, hidrofobia e desidratação podem ser considerados como responsáveis pela insuficiência renal aguda na raiva.

Ultrastructure of cranial nervs of rats inoculated with rabies virus

The V and VII cranial nerves of rats inoculated with rabies virus were studied by electron microscopy. The results were compared with the same cranial nerves of rats inoculated with rabies virus but vaccinated against the disease. The findings are those of axonal degeneration and intense demyelination of the nerves of the group of rats not vaccinated. The vaccinated rats showed some ultrastructural irrelevant alterations when compared with the other group. The degreee of ultrastructural alterations found in the group of rats not vaccinated suggests that in rabies severe damage of the cranial nerves occurs and that this may be closely related to the clinical picture of the disease (hydrophobia). Furthermore, as far as the authors know, this has not been considered in the classic descriptions of rabies and it is possible that an immunologic process may take part in the demyelination observed in the present study.

Detección del antígeno viral de la rabia por el método avidina - biotina - peroxidasa / Detection of the rabies viral antigen by the avidin - biotin - peroxidase method

Antecedentes: La rabia humana y animal es frecuente en Colombia. Su diagnóstico requiere inmnofluorescencia directa (IFD) e inoculación intracerebral al ratón (IIC), condiciones que alcanzan pocos laboratorios. La histopatología muestra cuerpos de Negri entre el 40 por ciento al 87 por ciento de los casos. Nuestro objetivo es desarrollar y determinar la utilidad del método avidina-biotina-peroxidasa (ABP) en tejido fijado en formol e incluido en parafina. Materiales y métodos: Se estandarizó la técnica ABP usando muestras de encéfalo con rabia confirmada por IFD, IIC al ratón o histopatología. La técnica se pudo a prueba estudiando cortes de 100 encéfalos humanos o de animales sospechosos de tener rabia. Se escogieron encéfalos incluídos en parafina o mantenidos en congelación durante años, SNC fresco de ratón inoculado con virus fijo y cerebros normales o con otras encefalitis virales. Se determinó la sensibilidad, la especificidad y la reproducibilidad del método. Resultados: La técnica de ABP muestra sensibilidad mayor o igual a .80 y especificidad mayor o igual a .97. La concordancia con respecto a la IIC y a la IFD dio resultados entre substanciales y casi perfectos, según la escala de Landys y Koch, niveles altos que también se obtienen al evaluar la reproducibilidad intraobservador e interobservador. La técnica fue siempre mejor que la HE. Conclusiones: La técnica es útil, confiable, reproducible, fácil de realizar y funciona bien inclusive en encéfalos con pobre preservación tisular. Merece incluirse entre los procedimientos de rutina o alternativos en el dignóstico de la rabia humana y animal