Dados do Trabalho

Título

Spatial Scan Analysis of Aedes aegypti Infestation: Efficiency of Ovitraps in Bahia and Minas Gerais Municipalities

Introdução

Dengue control heavily depends on the efficient monitoring of Aedes aegypti, and the use of ovitraps for egg counting enables early identification and the implementation of targeted control measures. In this context, the need for continuous and effective surveillance strategies to mitigate the spread of the disease is highlighted.

Objetivo (s)

To describe the infestation behavior of Aedes in households in the municipalities of Icaraí (MG) and Itatim (BA), as well as the application of spatial scan analysis to evaluate infestation hotspots. 

Material e Métodos

In the municipality of Itatim, the study was conducted from 11/29/23 to 3/21/24, with PneuTrap3D® traps distributed in 100 households, inspected every 15 days. In Icaraí, 75 households received PneuTrap3D® traps, monitored from 1/20 to 5/8/24, totaling 525 traps examined, inspected every 15 days. During inspections, trap paddles were collected and sent to the laboratory for egg counting, with the ovitrap positivity index (IPO) expressed as a percentage and the egg density index (IDO) expressed as the number of eggs per positive trap. A space-time analysis using the spatial scan technique for a Bernoulli distribution was applied to the number of eggs, evaluating the presence of high-count clusters (SaTScan 10.1 software)

Resultados e Conclusão

The average IPO for Itatim was 24.3±7.3 (range 16.8 to 40.6), and the average IDO was 36.9±12.2 (range 20.8 to 54.9). Spatial scan analysis detected two high-count clusters of eggs, one with 24 households from 1/26/24 to 3/21/24 and a radius of 0.18 km, and another with three households from 3/1/24 to 3/21/24 and a radius of 0.04 km. In Icaraí, the average IPO was 62.1±7.4 (range 53.3 to 69.3), with an average IDO of 13.7±3.2 (range 10.1 to 19.8). Spatial scan analysis detected two high-count clusters of eggs, one with 27 households from 1/20 to 2/21 and a radius of 0.48 km, and another with ten households from 2/15 to 3/27 and a radius of 0.18 km. The results of this study confirm the effectiveness of ovitraps and spatial analysis in identifying Aedes aegypti hotspots. The variation in indices highlights the need for localized and continuous control strategies to reduce dengue outbreaks.

Palavras Chave

Aedes aegypti Monitoring; Spatial Scan; Dengue Control