Title

The malaria ecosystem in southern Mexico

Date of Completion

January 1998

Keywords

Anthropology, Cultural|Biology, Ecology|Health Sciences, Public Health

Degree

Ph.D.

Abstract

This dissertation examines the malaria ecosystem in the Soconusco Foothills region, Chiapas, in Southeastern Mexico. My research was part of a multidisciplinary study of a region hyperendemic with malaria in which scientists from Mexico's Malaria Research Institute, the Pan-American Health Organization, and the World Health Organization collaborated with residents in five communities in a three-year longitudinal study (1989-1991). I test Steven Ault's model of the malaria system with two datasets: (1) A case-control malaria risk assessment/human mobility study (n = 100 malaria cases, 200 non-infected controls); and, (2) a household-level malaria ecosystem study (N = 70 households with malaria cases ranging from 0-15 cases). Data analysis employed univariate descriptors of location, dispersion, and distributional characteristics, bivariate LOWESS smoothing plots, multivariate factor, cluster analysis data reduction and, for model testing, multivariate Quadratic Assignment Procedures and multiple logistic regression. Household and individual incidence of malaria increases with proximity to the principal vector breeding area. Use of bednets significantly reduced the likelihood of malaria among individuals. Household socioeconomic status affects the likelihood of malaria. Poorer people live closer to principal breeding areas; live in larger households, and spray insecticides less often.^ Ethnographic data suggest that parasite reservoirs are perpetuated because of inconsistent treatment compliance resulting from (1) an ineffective combination of western and non-western home-based malarial treatment, and, (2) varying individual views of treatment efficacy characterized by confidence, speed and past experience with therapies. Finally, participants did not see malaria as a significant problem. Rather, economic viability, debt/credit, household subsistence, contaminated water, transportation, disposable cash, and other debilitating illnesses including lingering high fevers and diarrhea were of far greater significance. ^