[Intestinal geohelminthosis in man and domestic animals in the riverside sections of the Valdivia River Basin, Chile].

: In March-October 1987 were analyzed 1295 coprological specimens in a sample of the human population who lives in riverside localities in the Valdivia River Basin, Chile. A 23.6% of examined persons presented infection by one or more helminth species. The prevalence of infection by Ascaris lumbricoides, Trichuris trichiura and Trichostrongylidae gen. sp. were 15.5, 12.7 and 0.2%, respectively. The prevalence of human ascariosis and trichuriosis were greater in pre-school and school children. The sex of the host and prevalence of geohelminthosis did not show any relationship. Prevalences of ascariosis and trichuriosis were higher in persons from houses with no sanitary fecal and water disposal. Over 35% and 20.7% of family groups showed infection by A. lumbricoides and T. trichiura, respectively in over 40% of the members of each group. Fecal samples from domestic mammals revealed the following prevalences rates for helminth infections: in dogs 19.0 and 15.2% for Toxocara canis and Uncinaria stenocephala respectively, in cats 65.1% for Toxocara cati, and in pigs 25.4 and 3.2% for Ascaris suum and Trichuris suis respectively. Some of these species are clearly demonstrated agents of zoonoses.