Spatial analysis of the natural infection index for Triatomines and the risk of Chagas disease transmission in Northeastern Brazil

• Published in: Revista do Instituto de Medicina Tropical de São Paulo Vol. 65; pp. e32 - 10
• Main Authors: Medeiros, Carolina de Araújo, Silva, Maria Beatriz Araújo, Oliveira, André Luiz Sá de, Alves, Sílvia Marinho Martins, Oliveira Júnior, Wilson de, Medeiros, Zulma Maria de
• Format: Journal Article
• Language: English; Portuguese
• Published: Brazil Instituto de Medicina Tropical de Sao Paulo 01.01.2023; Instituto de Medicina Tropical de São Paulo
• Subjects: Animals; Brazil - epidemiology; Chagas Disease; Disease transmission; Ecological studies; Ecosystems; Epidemiology; Humans; Infections; Insect Vectors; Insects; Laboratories; Original; Panstrongylus; Protozoa; Public health; Spatial Analysis; Triatoma; TROPICAL MEDICINE; Trypanosoma cruzi; Urbanization; Brazil; Chagas disease; Spatial analysis; Epidemiology; Triatomine
• ISSN: 1678-9946; 0036-4665; 1678-9946
• DOI: 10.1590/S1678-9946202365032

This study aimed to analyze the spatial pattern of natural infection index (NII) for triatomines and the risk of Chagas disease transmission in an endemic area of Northeastern Brazil. An ecological study was conducted, based on 184 municipalities in five mesoregions. The NII for triatomines was evaluated in the Pernambuco State, Brazil, from 2016 to 2018. Spatial autocorrelations were evaluated using Global Moran Index (I) and Local Moran Index (II) and were considered positive when I > 0 and p < 0.05, respectively. In total, 7,302 triatomines belonging to seven different species were detected. Triatoma brasiliensis had the highest frequency (53%; n = 3,844), followed by Triatoma pseudomaculata (25%; n = 1,828) and Panstrongylus lutzi (18.5%; n=1,366). The overall NII was 12%, and the higher NII values were P. lutzi (21%) and Panstrongylus megistus (18%). In the mesoregions of Zona da Mata, Agreste, Sertao, and Sertao do Sao Francisco, 93% of triatomines were detected indoors. The global spatial autocorrelation of I to NII was positive (0.2; p = 0.01), and II values calculated using BoxMap, MoranMap, Lisa Cluster Map were statistically significant for natural infections. With regard to the risk areas for the presence of triatomines, Zone 2 (the Agreste and Sertao regions) presented a relative risk of 3.65 compared to other areas in the state. Our study shows the potential areas of vector transmission of Chagas disease. In this study, the application of different methods of spatial analysis made it possible to locate these areas, which would not have been identified by only applying epidemiological indicators.