Dengue fever: a post-epidemic sero-epidemiological survey in an urban setting at a northwestern county of S. Paulo State - Brazil

Objective The objective of this study was to evaluate the real size of the epidemics registered in thr urban area of the county of Santa Barbara D'Oeste, SP Brazil, from April to June, 1995. The measurement of the epidemiological validity of the official surveillance system criteria and its positive predicted value It were adopted as specific goals. Methods A sero-epidemiological sun,ey was carried out over a sample of 1,113 sera from citizens of Santa Barbara D'Oeste, through a systematic random sampling of houses, five months after the end of the epidemics. Infection rates were compared with the infestation indexes by Aedes aegipty and the notified cases amongst the county sections. The importance of submitting patients with clinical suspicion of dengue to laboratory rests was discussed. Results and Discussion it was found that infection rates by dengue virus varied in the same direction and proportion as the presence of Aedes aegipty larvae reported by the 'Breteau Index', as well as the number of cases,reported by the official notifiable diseases surveillance system during the epidemics. A prevalence of 630 by 100 thousand inhabitants was found, a 15-fold rate when compared to rite laboratory positive sera from cases detected by the surveillance system during the epidemics. A retrospective comparison with the surveillance reports, using serological results as a gold standard, also showed that the majority of dengue specific serum-positive individuals were not detected during the epidemics. otherwise cases that did not present serological reaction were notified exhibiting a low positive predictive value of clinical diagnosis (15,6).33656657

Mispatterning in the ommatidia of Apis mellifera pupae treated with a juvenile hormone analogue

To further understand the function of morphogenetic hormones in honeybee eye differentiation, the alterations in ommatidial patterning induced by pyriproxyfen, a juvenile hormone (JH) analogue, were studied by scanning and transmission electron microscopy. Prepupae of prospective honeybee workers were treated with pyriproxyfen and the effects on ommatidial differentiation were described at the end of the pupal development. The results show that the entire ommatidia, i.e., the dioptric as well as the receptor systems, were affected by the JH analogue. The wave of ommatidial differentiation, which progresses from the posterior to the anterior region of the pupal eyes, was arrested. In treated pupae, the rhabdomeres only differentiated at the apical axis of the retinula, the secondary and tertiary pigment cells did not develop their cytoplasm protrusions, and the cone cell quartet did not pattern correctly. Simultaneously, an intense vacuolization was observed in cells forming ommatidia. In a previous study we showed that pyriproxyfen exerts an inhibition on pupal ecdysteroid secretion. In this sense, the arrested ommatidial differentiation in pyriproxyfen-treated pupae could be due to a secondary effect resulting from an alteration in pupal ecdysteroid titers. J. Morphol. 249:89-99, 2001. (C) 2001 Wiley-Liss, Inc

Padronização e uso de um método imunoenzimático que utiliza células infectadas como antígeno no diagnóstico rotineiro do dengue Standardization and use of an immunoenzymatic method using infected cells as antigens in routine diagnosing of dengue

INTRODUÇÃO: Este trabalho mostra a padronização e o uso do método imunoenzimático utilizando células infectadas como antígeno (EIA-ICC) no diagnóstico sorológico rotineiro do dengue. MÉTODOS: Na otimização do teste, com a dose de 1.000 TCID50 de vírus do dengue tipo 3 (DENV-3), foram utilizadas 100.000 células C636 infectadas 1000 TCID50 (DENV-3). RESULTADOS: Os resultados obtidos com EIA-ICC foram comparados com o kit comercial de dengue HUMAN. Os resultados foram altamente coincidentes; o EIA-ICC mostrou-se moderadamente sensível e com alta especificidade. O teste foi usado no diagnóstico sorológico de 1.797 amostras sorológicas de casos suspeitos de dengue durante a epidemia de Ribeirão Preto, em 2006. Na avaliação sorológica, 228 amostras foram positivas para IgM contra DENV-3, e 235 amostras foram positivas para IgG contra DEV-3, e em 35 amostras detectou-se positividade para IgM e IgG. CONCLUSÕES: O EIA-ICC mostrou-se confiável e simples sendo adequado ao diagnóstico sorológico do dengue.<br>INTRODUCTION: This paper show the standardization and use of the immunoenzymatic method using infected cells as antigens (EIA-ICC) for routine serological diagnosing of dengue. METHODS: In optimizing the test, a dose of 1,000 TCID50 of dengue type 3 virus (DENV-3) was used, and 100,000 C636 cells infected with 1,000 TCID50 (DENV-3) were used. RESULTS: The results obtained with EIA-ICC were compared with the HUMAN commercial dengue kit. The results were highly concordant. The EIA-ICC showed moderate sensitivity and high specificity. The test was used for serologically diagnosing 1,797 blood samples from suspected dengue cases during the 2006 epidemic in Ribeirao Preto. From the serological evaluation, 228 samples were positive for IgM against DENV-3; 235 samples were positive for IgG against DENV-3; and 35 samples were positive for both IgG and IgM. CONCLUSIONS: EIA-ICC was shown to be reliable and simple, and suitable for serologically diagnosing dengue

Dengue: inquérito populacional para pesquisa de anticorpos e vigilância virológica no Município de Campinas, São Paulo, Brasil Dengue: sero-epidemiological survey and virological surveillance in Campinas, São Paulo, Brazil

Estudou-se a epidemiologia do dengue no Município de Campinas, São Paulo, Brasil, por meio de um inquérito populacional aleatório realizado em 1998, visando à detecção dos níveis de anticorpos para dengue, e de dados de vigilância epidemiológica do período de 1996 a 2003, com ênfase na vigilância virológica. Foram coletadas 1.260 amostras, por meio de punção digital, utilizando-se papel de filtro, sendo as amostras testadas pelo teste imunoenzimático em culturas celulares infectadas (EIA-ICC). Observou-se que a prevalência de soro reagentes (14,79%) é mais baixa que as encontradas em outros inquéritos realizados no país e superior às encontradas em dois inquéritos realizados em cidades do Estado de São Paulo. Detectou-se uma prevalência de soro reagentes muito superior à incidência de casos notificados e confirmados laboratorialmente durante as epidemias de 1996, 1997 e 1998. Não se encontrou proporcionalidade entre a prevalência de anticorpos para dengue e a incidência de casos durante a epidemia nos diferentes Distritos de Saúde da cidade. Sugerem-se um estudo aprofundado do significado dos indicadores de transmissão utilizados em epidemias e uma vigilância virológica mais intensa, principalmente em anos com níveis de transmissão baixos.<br>The epidemiology of dengue in the municipality of Campinas, São Paulo, Brazil, was studied in 1998 using a randomized sero-epidemiological survey. Epidemiological surveillance data from 1996-2003 were also analyzed, with an emphasis on virological surveillance. 1,260 individuals participated in the survey and had blood samples drawn by finger stick on filter paper. Blood samples were tested by EIA-ICC, an enzyme immunoassay using infected cells as antigen. Dengue antibody prevalence (14.79%) was lower than in other surveys in other States of Brazil, but higher than in two other serological surveys in São Paulo State. Dengue antibody prevalence was far higher than the reported case incidence during the 1996, 1997, and 1998 epidemics. Antibody prevalence and reported case incidence in different health districts were disproportional. The article concludes by recommending further research on the significance of transmission rates during epidemics and more intensive virological surveillance, especially in years with few reported cases