Factors associated with the incidence of malaria in settlement areas in the district of Juruena, Mato Grosso state, Brazil

Abstract

Factors associated with the incidence of malaria in settlement areas in the district of Juruena, Mato Grosso state, BrazilFatores associados à incidência da malária em área de assentamento, município de Juruena, Mato Grosso, Brasil

Malaria incidence and assessment of entomological indices among resettled communities in Ethiopia: a longitudinal study

“…Other studies have also reported increase in malaria incidence and an increase in malaria affected people as a result of population resettlement [ 20 ]. In studies conducted in Brazil, reemergence of malaria was noted as a result of resettlement [ 21 , 22 ]. Similarly, in another study conducted in Somalia [ 23 ], a significant increase in malaria prevalence was reported following influx of non-immune people in to malaria endemic areas.…”

Situação da malária na tríplice fronteira entre Brasil, Colômbia e Peru

“…Por outro lado, o predomínio de casas de alvenaria e telhado industrial e o uso disseminado de mosquiteiros dificulta o contato com o vetor, o que podem ser consideradas fortalezas tanto para Tabatinga quanto para Leticia, como foi também encontrado por Ferreira et al 19 . Alexander et al 20 em um estudo de casos e controles e aplicando um modelo multivariado, mostraram que o uso de mosquiteiros impregnados esteve associado a uma redução de 56% dos casos de malária quando comparados com a população que não usou estas tecnologias.…”

The impact of industrial activities on vector-borne disease transmission

“…Occupational exposure to vector-borne diseases was documented as early as the 1850s during the construction of the Panama Railroad, when an estimated 12,000 workers died due to vector-borne diseases (malaria and yellow fever) from 1850 to 1855 (McCullough, 1977). More recently, an analysis of factors associated with malaria in Juruena, Matto Grosso, Brazil, in 2005 found that infection prevalence was higher in individuals working in mining activities than observed for house workers (Ferreira et al, 2012), indicating that mining activities place workers at greater risk of contracting malaria. In the Americas as a whole, 60% of malaria cases occurred in men in 2014, and younger men are more at risk of malaria infection, consistent with the period of life in which individuals are exposed to the highest densities of vectors because of their work (Barbieri et al, 2005;Ferreira et al, 2012;Pan American Health Organization, 2014).…”

“…Migrants may be more biologically vulnerable than indigenous populations in malaria endemic areas because of a lack of naturally-acquired immunity developed from previous infections. For instance, in Juruena malaria prevalence in a mining settlement was 56% greater in individuals coming from non-endemic areas than in those that originated from malaria endemic areas (Ferreira et al, 2012). Indeed, it was the 'transient nonimmune' population during the Pailin gem rush of the 1950s and 60s that was thought to fuel the emergence of chloroquine resistance in Western Cambodia (Verdrager, 1986).…”

“…One of the consequences of the migratory nature of mine workforces, formal or informal, is the difficulty of disease surveillance for measuring disease burden. Active case detection implemented by the Brazilian government has been credited with a dramatic reduction in malaria incidence in Mato Grosso from 96.1 to 2.7 cases per 1,000 inhabitants from 1992 to 2002 (Ferreira et al, 2012). Case monitoring can be interrupted or complicated by migration and periodic movement of mine workers, i.e., those who may be missed completely or who may be labelled as imported cases elsewhere.…”