Dados do Trabalho

Título

Arbovirus underreporting in a hyperendemic area of Brazil: a population-based survey and implications for public health surveillance

Introdução

The multifaceted interplay of vector-borne viruses, such dengue vírus (DENV), Zika vírus (ZIKV), and chikungunya vírus (CHIKV), imposes a significant global burden, particularly in tropical regions like Brazil. The diagnostic complexity and surveillance challenges necessitate comprehensive strategies. Although seroepidemiological studies have predominantly focused on regions like the Northeast and Southeast, there is a notable gap in the Midwest, where dengue incidence remains high. São Sebastião, located within the Federal District, is a significant epicenter of dengue cases, potentially underreported due to asymptomatic infections. Our seroepidemiological study aims to address this gap by estimating disease prevalence and comparing it with surveillance data, shedding light on disease dynamics and spatial distribution.

Objetivo (s)

We estimated the seroprevalence of DENV, ZIKV and CHIKV in São Sebastião and compared it with surveillance data. Furthermore, we analyze the spatial distribution and highlight the diagnostic challenges for these arboviruses in endemic areas.

Material e Métodos

A cross-sectional study was conducted in São Sebastião Federal District, sampling 1,535 households. ELISA serological testing for DENV, ZIKV, and CHIKV was performed. Statistical analysis included normality tests, associations, comparison of means and correlations. Spatial analysis utilized geocoded data for heat map generation via kernel quartic function in QGIS, reclassified to accurately depict case density.  

Resultados e Conclusão

The study covered 1,405 individuals, divided into pre-pandemic and pandemic phases. Results indicated that advancing age and lower education were associated with increased exposure to arboviruses. High rates of seropositivity for DENV, ZIKV, and CHIKV were observed, with frequent co-occurrence. Antibody profile analysis revealed stages of infection and testing limitations. Notable disparities were found between manufacturers in estimating ZIKV seroprevalence. Spatial analysis indicated that housing conditions and urban planning influence case occurrence. Significant underreporting of chikungunya cases suggests the true infection rate may be substantially higher. The underreporting of arbovirus cases in the evaluated area reveals a significant gap in epidemiological surveillance. This condition negatively impacts the allocation of health resources and the implementation of effective interventions.

Palavras Chave

vector-borne viruses; seroepidemiologic studies; arboviruses and epidemiological surveillance