Estudo retrospectivo da doença de Chagas e seus vetores na região sul do Rio Grande do Sul, Brasil

Abstract

Chagas disease (CD) caused by the protozoan Trypanosoma cruzi is identified by the World Health Organization (WHO) as one of the most neglected tropical diseases in the world. Rio Grande do Sul is a region considered endemic for DCH and was the Brazilian state that presented the highest human seroprevalence index for T. cruzi. In view of this, it is important to assess the epidemiological situation of DCH in the southern region of the state of Rio Grande do Sul, both in relation to the characterization of vectors (main captured species, T. cruzi infection rate, invasion sites/ infestation) such as the prevalence of DCH among blood donors and the CD mortality rate in the region. The study area comprises the municipalities covered by the 3rd Regional Health Coordination (CRS) and 7th CRS. The research related to DCH vectors was based on the analysis of secondary data made available by the State Health Surveillance Center of Rio Grande do Sul (CEVS-RS). To assess the prevalence of IgG anti-T. cruzi antibodies among blood donors in the southern region, a study was carried out at the Blood Center in the city of Pelotas/RS, as this covers both the 3rd CRS and the 7th CRS donors. And in relation to the mortality rate from CD in the region, the program consulted was the SIM (Mortality Information System) of DATASUS (Department of Informatics of the Unified Health System). In the period from 2008 to 2019, in the 3rd CRS, a total of 1400 triatomines were captured, the municipalities with the highest number of captures were Canguçu (37.7%), Piratini (22.4%) and Pinheiro Machado (15.1% ). The municipality of the 7th CRS with the most capture was Lavras do Sul (64.2%). The species with the highest number of specimens found were Triatoma rubrovaria (90.6%), followed by Panstrongylus tupynambai (7.4%), in both CRS. The southern region of RS continues to present important home invasion and dispersion of triatomines, especially by the species T. rubrovaria, followed by P. tupynambai, requiring greater surveillance of these vectors. Regarding the prevalence of DCH among blood donors in the southern region, the rate of discarding blood bags due to positive or inconclusive reactions to anti-T. cruzi, in the Regional Blood Center of Pelotas, in a period of 10 years, was 0.26% (283 bags), and individuals from the municipalities of Canguçu and Pelotas stand out in relation to the largest number of seroreactive donors for anti-IgG antibodies T.cruzi. Regarding mortality from CD in the southern region, in the municipalities covered by the 3rd CRS (Pelotas), there was a total of 60 (16.5%) deaths, in the 7th CRS (Bagé), the mortality was 2.5% (9 cases ). The municipalities with the highest mortality rate from CD in the were: Pelotas, Canguçu, Rio Grande and Lavras do Sul. It can be seen that both CD and its vectors continue to be important in RS, with no oversight being admitted with regard to triatomine surveillance and serological control in blood banks.