Seroprevalencia del dengue en el distrito de Casma. Ancash, Perú 2002

Abstract

Objectives: To assess the extent of dengue fever virus infection after the first outbreak that occurred in Casma District, Ancash (February to April 2002). Materials and methods: A seroepidemiological study was performed after the outbreak, 400 blood specimens obtained using a probabilistic, two-staged and conglomerate sampling technique were collected in filter paper, and they were analyzed for this study. A patient was considered as infected if a positive result in the IgM and IgG capture-ELISA for dengue fever was found. Results: Prevalence of dengue fever infection on the basis of this seroepidemiological survey was 14,1% (95% confidence interval [CI]: 9,8–18,4%). Consequently, it is estimated that 3939 cases of dengue fever serotype 1 infection occurred in Casma District during the outbreak from February to May 2002. 60% of all positive cases developed symptoms, the Epidemiological Surveillance system reported only 832 cases of classic dengue fever and no severe cases were found. Conclusions: Seroprevalence in the first dengue fever outbreak in Casma District in April 2002 was 14,1% The epidemiological surveillance system detected 21% of the total estimated number of infected persons (approximately 1:5); and 32,5% of cases that developed symptoms.