Determinação do perfil antigênico de 3 cepas de vírus rábico, isoladas no Brasil, através da técnica dos anticorpos monoclonais antinucleocapside

Determinou-se, através da técnica dos anticorpos monoclonais , o perfil antigênico antinucleocapside de 3 cepas de vírus rábico, isoladas no Brail, com o auxílio da técnica de imunofluorescência indireta. Duas das cepas eram de origem de cão, uma delas procedente da cidade de Jales, SP, e a outra oriunda da Nigéria, África. A terceira cepa era de origem de morcego, identificada com DR 19 e considerada como cepa intermediária entre as fixas e as naturais. Os resultados obtidos evidenciaram diferenças pronunciadas entre as 3 cepas, caracterizando-as como distintas antigenicamente, mas com perfil antigênico característico das cepas rábicas. Os resultados confirmaram, também, procedência da cepa Nigéria, uma vez que seu perfil antigênico coincidiu com daquelas isoladas em seu país de origem. As cepas Jales e Nigéria, embora originárias de uma mesma espécie animal, mas procedentes de regiões diferentes, apresentaram os perfis antigênicos nucleocapside distintos.A study was conducted to determine the nucleocapside antigenic characteristics, by the monoclonal antibodies technique, of 3 rabies virus strains, isolated in Brazil. Two of them were isolated from dogs, one from Jales city, in São Paulo state, and the other, from Nigeria, Africa. The third strain, DR 19, was isolated from brazilian vampire bat and has been considered as an intermediary strain. All the strains were identified as antigenically different, but with all characteristics of the rabies virus strains. The Nigerian strain was confirmed as an African strain. In the other hand, the Jales and Nigeria strains, both isolated from dogs, but from differents regions, showed pronounced differences in the nucleocapside antigenic characteristics

Evaluation of ERA anti-rabies vaccine against four different antigenic strains of rabies virus in mice

Estudou-se a eficácia da vacina anti-rábica preparada em cultura primária de tecido renal de suínos, a partir da amostra ERA, na prevenção da raiva em camundongos, frente a quatro cepas antigenicamente distintas do vírus rábico, duas originadas de cão. C/SP e C/NG, uma originada de morcego, DR-19, e uma cepa fixa, CVS (Challenge Vírus Standard). O perfil antigênico desta cepa foi determinado pela técnica dos anticorpos antirrábicos monoclonais antinucleocapside. Os animais foram vacinados, aos 21 dias de idade, por via intramuscular na face interna da coxa, com uma única dose de 0,05 ml de vacina e desafiados aos 42 dias de idade, em conjunto com os animais do grupo testemunho, por via intramuscular na face interna da coxa, com 0,05 ml da suspensão da cepa viral correspondente. Os resultados obtidos permitiram constatar que a vacina ERA protegeu 100% dos animais desafiados com as cepas C/SP, C/NG e DR-19 e 83% dos animais desafiados com à cepa CVS, enquanto que a mortalidade no grupo testemunho variou entre 70 e 90%.ERA anti-rabies vaccine prepared in kidney tissue culture was evaluated against four different antigenic strains of rabies virus in mice: two of them dog strains, C/SP and C/NG, another a bat vampire strain, DR-19, and the CVS strain. The CVS antigenical characteristics were determined by means the antinucleocapsid monoclonal antibodies technique. Twenty one days old mice were vaccinated, intramuscularly, in the inner side of the thigh, with 0.05 ml of vaccine and challenged at 42 days old, together with those of the control group, intramuscularly, in the inner side of the thigh, with 0.05 ml of the corresponding viral strain dilution. The ERA anti-rabies vaccine protected 100% of all the mice challenged with C/SP, C/NG and DR-19 strains and 83% of those challenged with CVS. The control groups mortality rate varied between 70 and 90%

Discovery and Description of Ebola Zaire Virus in 1976 and Relevance to the West African Epidemic During 2013-2016.

BACKGROUND: In 1976, the first cases of Ebola virus disease in northern Democratic Republic of the Congo (then referred to as Zaire) were reported. This article addresses who was responsible for recognizing the disease; recovering, identifying, and naming the virus; and describing the epidemic. Key scientific approaches used in 1976 and their relevance to the 3-country (Guinea, Sierra Leone, and Liberia) West African epidemic during 2013-2016 are presented. METHODS: Field and laboratory investigations started soon after notification, in mid-September 1976, and included virus cell culture, electron microscopy (EM), immunofluorescence antibody (IFA) testing of sera, case tracing, containment, and epidemiological surveys. In 2013-2016, medical care and public health work were delayed for months until the Ebola virus disease epidemic was officially declared an emergency by World Health Organization, but research in pathogenesis, clinical presentation, including sequelae, treatment, and prevention, has increased more recently. RESULTS: Filoviruses were cultured and observed by EM in Antwerp, Belgium (Institute of Tropical Medicine); Porton Down, United Kingdom (Microbiological Research Establishment); and Atlanta, Georgia (Centers for Disease Control and Prevention). In Atlanta, serological testing identified a new virus. The 1976 outbreak (280 deaths among 318 cases) stopped in 2 years. Transmission indices (R0) are higher in all 3 countries than in 1976. CONCLUSIONS: An international commission working harmoniously in laboratories and with local communities was essential for rapid success in 1976. Control and understanding of the recent West African outbreak were delayed because of late recognition and because authorities were overwhelmed by many patients and poor community involvement. Despite obstacles, research was a priority in 1976 and recently

Update of the statements on biology and clinical impact of occult hepatitis B virus infection

Summary In October 2018 a large number of international experts with complementary expertise came together in Taormina to participate in a workshop on occult hepatitis B virus infection (OBI). The objectives of the workshop were to review the existing knowledge on OBI, to identify issues that require further investigation, to highlight both existing controversies and newly emerging perspectives, and ultimately to update the statements previously agreed in 2008. This paper represents the output from the workshop

Compte rendu de la réunion d'information et du débat sur la documentation en mathématiques

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