Retrospective study on dengue in Fortaleza, State of Ceará, Brazil

A retrospective serologic study was carried out in Fortaleza, State of Ceará, Brazil, in order to detect the dengue virus activity before recognizing the epidemic of 1994. Mac-Elisa was performed by using a mixture of specific DEN-1 and DEN-2 antigens on serum samples from the Emilio Ribas Laboratory collection. Samples were obtained from 1,224 patients with exanthematic febrile disease and negative serological results for rubella. All specimens were taken during November 1993 to May 1994. The results confirmed dengue infections in Fortaleza by November 1993, approximately six months before the beginning of the epidemic, proving how misleading diagnosis of dengue infection are still troublesome, in spite of the strong dengue activity in Ceará. The authors stress the urgent necessity to implement the active surveillance system in order to prevent another extensive fever epidemics in the state. Epidemiological background of the dengue activity in the State of Ceará is also described.

Dengue infection in Paracambi, State of Rio de Janeiro, 1990-1995

Um inquérito soroepidemiológico foi realizado em uma amostra de escolares, em 1994, no município de Paracambi, Estado do Rio de Janeiro. Positividade do teste de Inibição da Hemaglutinação foi detectada em 39,2% (145/370) dos escolares pesquisados. A freqüência de positividade foi de 53,8% (78/145) para o sexo feminino e de 46,2% (67/145) para o sexo masculino. A distribuição por faixa etária mostrou uma positividade crescente com o aumento da idade. Cepas do vírus dengue tipo 1 e vírus dengue tipo 2 foram isoladas anteriormente (1990), mostrando a co-circulação de ambos os sorotipos na área. Os índices de infestação predial pelo Aedes aegypti e pelo Aedes albopictus foram determinados.

A seroepidemiological survey was carried out during 1994 in the municipality of Paracambi, state of Rio de Janeiro. Haemagglutination inhibition test positivity was detected in 145 out of 370 (39.2%) schoolchildren. The frequency of positive test by sex was 53.8% (78/145) female and 46.2% (67/145) male. Distribution by age showed the increasing of antibody positivity in older children. Strains of dengue virus type 1 and dengue virus type 2 were isolated before (1990) showing the co-circulation of both serotypes in that area. The house index infestation of Aedes albopictus and Aedes aegypti has been determined.