RESUMO
Within 72 hours of visiting the Everglades National Park in south Florida, a 43-year-old man became ill with fever, malaise, myalgia, severe headache, pharyngitis, and enlarged, tender lymph nodes. Everglades (Venezuelan equine encephalomyelitis, subtype II) virus was isolated from a blood sample drawn from the patient five days after onset of symptoms.
Assuntos
Encefalomielite Equina/diagnóstico , Encefalomielite Equina Venezuelana/diagnóstico , Adulto , Testes de Fixação de Complemento , Testes de Inibição da Hemaglutinação , Humanos , MasculinoRESUMO
La Crosse virus cell culture-derived soluble antigen was used in a counterimmunoelectrophoresis procedure to assess the presence or absence of La Crosse antibodies in 79 paired acute- and convalescent-phase human sera. The counterimmunoelectrophoresis test appeared to measure the same antibody as the complement fixation test but was more sensitive and rapid.
Assuntos
Anticorpos Antivirais/análise , Vírus da Encefalite da Califórnia/imunologia , Vírus da Encefalite/imunologia , Encefalite por Arbovirus/diagnóstico , Encefalite da Califórnia/diagnóstico , Antígenos Virais , Testes de Fixação de Complemento , Contraimunoeletroforese , HumanosRESUMO
A virus-free soluble antigen, obtained by ammonium sulfate precipitation of the supernatant fluids of La Crosse virus-infected BHK-21 cell cultures, was more reactive and more specific than infected suckling mouse brain antigen when compared by immunodiffusion and counterelectrophoresis tests. By complement fixation tests, the antigen was cross-reactive with heterologous California group arbovirus hyperimmune mouse ascitic fluids, but to a lesser degree than was the standard sucrose-acetone-extracted infected suckling mouse brain antigen. The major virion nucleocapsid protein of La Crosse virus was found by polyacrylamide gel electrophoresis to be the soluble antigen protein responsible for precipitation in immunodiffusion and counterelectrophoresis tests.
Assuntos
Antígenos Virais , Vírus da Encefalite da Califórnia/imunologia , Vírus da Encefalite/imunologia , Capsídeo/imunologia , Testes de Fixação de Complemento , Contraimunoeletroforese , Reações Cruzadas , ImunodifusãoRESUMO
The serum dilution neutralization test was evaluated for serological diagnosis of California group arbovirus infections and identification of virus isolates. The technical advantages and the degree of subtype specificity of the serum dilution neutralization test over the hemagglutination inhibition test and the complement fixation test were demonstrated with paired specimens from human cases, single human survey sera, and sentinel rabbit sera. Twenty-one virus isolates from various geographical areas of the United States were also used to evaluate the efficacy of the serum dilution neutralization test for specific virus identification.
Assuntos
Infecções por Arbovirus/diagnóstico , Vírus da Encefalite da Califórnia/imunologia , Vírus da Encefalite/imunologia , Testes de Neutralização , Adolescente , Adulto , Anticorpos Antivirais/análise , Criança , Pré-Escolar , Testes de Fixação de Complemento , Reações Cruzadas , Diagnóstico Diferencial , Estudos de Avaliação como Assunto , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Lactente , MasculinoAssuntos
Arbovírus/classificação , Aedes , Alaska , Animais , Antígenos Virais , Arbovírus/crescimento & desenvolvimento , Arbovírus/imunologia , Arbovírus/isolamento & purificação , Sangue/microbiologia , Linhagem Celular , Testes de Fixação de Complemento , Reações Cruzadas , Culicidae , Efeito Citopatogênico Viral , Ecologia , Feminino , Haplorrinos , Rim , Camundongos , Testes de Neutralização , Coelhos , Terminologia como AssuntoRESUMO
Human sera were treated with kaolin, acetone, and dextran sulfate to determine the best method for removing nonspecific hemagglutination inhibitors. Results indicated that on surveys for group A, group B, and some group C arbovirus HI antibodies, dextran sulfate treatment of sera could be used effectively. This method, however, has limited usefulness for detecting HI antibody for a number of arboviruses, particularly some members of the Bunyamwera supergroup since nonspecific inhibitors for these antigens were not completely removed. HI antibodies in sera drawn early after dengue and Venezuelan equine encephalitis infection were detected more readily after dextran sulfate treatment than after kaolin treatment. Kaolin, but not dextran sulfate, was shown to remove antibody from IgM fractions of sera.
