The effects of local medicinal knowledge and hygiene on helminth infections in an Amazonian society

Social science has long recognized the importance of understanding how interactions between culture and behavior shape disease patterns, especially in resource-poor areas where individuals draw on multiple medical treatments to maintain health. While global health programs aimed at controlling high infection rates of soil-transmitted helminthes among indigenous groups often acknowledge the value of local culture, little research has been able to examine this value. This study investigates the association between parental ethnomedical knowledge, parental biomedical knowledge, and household sanitation behavior and childhood soil-transmitted helminth infections among a group of foragers–farmers in the Bolivian Amazon (Tsimane’). During 2007, a parasitological survey was completed for 329 children (≤16 years of age) from 109 households in combination with a comprehensive survey of both of the child’s parents to assess biomedical and ethnomedical knowledge and household sanitary environment. Soil-transmitted helminthes were found to be common with 67% of sample positive for hookworm species. Indices that capture a household’s relative state of risky and preventive hygienic behavior were significantly associated with risk of hookworm infection. Mother’s but not father’s ethnomedical knowledge was also negatively associated with a child’s probability of being positive for hookworm infection. The effect was stronger for young children and boys. Like many rural populations, Tsimane’ actively draw upon multiple medical systems to respond to health challenges. Integration into markets and national societies is likely to affect local medical systems by increasing the use of biomedicine as formal education prioritizes biomedical over ethnomedical systems. This study underscores the value of considering both ethnomedical knowledge systems and household hygiene in public health campaigns to treat and control soil-transmitted helminths. There is no question that providing medication is critical, but this study demonstrates that poverty is not synonymous with either poor hygiene or the lack of valuable ethnomedicinal knowledge.

Research highlights
► This research measures the effects of ethnomedical knowledge on people’s responses to common diseases.
► Hookworm infection affected 67.2% of children and adolescents in the sample.
► Child risk of infection with hookworm was related to mother’s ethnomedical knowledge and household hygiene levels.
► No association was found between parent’s biomedical knowledge and risk of childhood infection.