Helminthiasis and culture change among the Cofán of Ecuador.
Blood and fecal samples and lifestyle interviews were obtained in August 1996 from two Cofán villages in Ecuador, Dureno and Zabalo, that are experiencing different degrees of acculturation. Dureno's territory has been divided by roads and encroached upon by oil companies and colonists, whereas Zabalo, 95 km downriver from Dureno, is located in the Cuyabeno Fauna Reserve, a protected area. This study examines how culture change affects the prevalence of parasitic infections. Fecal samples were examined for helminth eggs to determine helminthiasis in each village sample. Seventy-four samples were collected (Dureno n = 50; Zabalo n = 24), representing 20% of the population in each village. Hemoglobin (Hb) levels and eosinophil counts were determined for all adult participants (Dureno n = 39; Zabalo n = 13). Microscopic examination of prepared samples revealed ova from two parasitic nematodes: roundworm (Ascaris lumbercoides) and hookworm (Ancylostoma duodenale or Necator americanus). Roundworm and hookworm infections were higher in Dureno (44% positive) compared to Zabalo (17% positive), with infected adults from both villages showing eosinophilia. Hb levels were not significantly correlated with the prevalence of helminth infections. It appears that the transmission and prevalence of parasitic infections within each community is associated with the interaction of biological, cultural, and environmental factors. Am. J. Hum. Biol. 12:465-477, 2000. Copyright 2000 Wiley-Liss, Inc.