Intestinal parasites in two indigenous ethnic groups in northwestern Amazonia

ABSTRACT Approximately 90% of the population in the northwestern Amazonia is composed of indigenous people and their healthcare is still a challenge. The objective of this study was to determine the frequency of parasites in two indigenous ethnic groups (Baré and Baniwa) in northwestern Amazonia. Stool samples from 270 individuals (199 Baniwa and 71 Baré) were analyzed using Richie's method and the spontaneous sedimentation method. Statistical differences among the proportions of infected individuals based on gender, age, and ethnicity were determined. All individuals were infected by protozoans or helminths. The most frequent parasites in the indigenous people were Ascaris lumbricoides (73%), Entamoeba spp. (53%), and Giardia intestinalis (48%). Protozoan parasites were more common among children aged 0-12 years; however, the frequency of helminths, such as hookworms and A. lumbricoides, was higher in adults. There were no significant differences in parasite frequencies between different genders or ethnic groups. Mixed infections by two or more protozoan and/or helminth species were detected in 96% of individuals. One individual was infected by 14 species. A high frequency of intestinal parasites was found in Baré and Baniwa ethnic groups. Improvements to infrastructure and health education programs are required to reduce risk of infection by intestinal parasites.