Epidemiological Profile of Malaria in a Rural Community From the Amazon of Mato Grosso

Abstract More than 95% of malaria transmission in Brazil occurs in the region called Legal Amazon constituted among other Brazilian states, including Mato Grosso, where, in 2015, 54% of the cases occurred in the municipality of Colniza, in the northwestern region of the state. Objetive: To describe the epidemiological profile of malaria in a rural community in the northwestern region of Mato Grosso, emphasizing its spatial pattern of occurrence. Methods: This is an ecological study covering information on the prevalence of plasmodium infection and on the use and occupation of soil by the population of the Três Fronteiras District, in the municipality of Colniza, Mato Grosso. Data were collected through a home visit in July 2011, with blood collection from the digital pulp for the preparation of a thick smear slide, completion of the SIVEP_Malaria notification form, for the construction of a georeferenced database with the software ArcGIS 9.2 (ESRI Corp.). The information was divided into use and occupation classes. In TerraView 3.14, a Kernel map was built to verify the density of cases and their location. Results: Of the 621 respondents, 68(11%) had plasmodium infection, 39(57.4%) of them by P. vivax, 27(39.7%) by P. falciparum and two (2.9%) with mixed infection. Among infected individuals, 49(72.1%) were men and 19(27.9%), women. The distribution of prevalent cases of infection by overlaying the map of occupation and use of land showed that the cases of malaria are distributed over the entire length of the district, with greater occurrence of cases per household in open areas, close to the mining company/artisanal mining. The kernel method, from the characterization of the spatial distribution pattern of malaria cases, allowed identifying areas of greater intensity of cases, whose so-called “hot” areas were located in the gold mining region. Conclusion: The transmission of malaria in the district of Três Fronteiras has a heterogeneous profile along its length, and the individuals residing in areas of mining, artisanal mining and timber extraction has increased frequency of infection by plasmodium, and its spatial pattern has a difference in the intensity of distribution of the disease.