Prevalence of intestinal helminthic infections in Kao District, north Halmahera, Indonesia

A parasitological survey was conducted on the inhabitants of six villages of Kao District, Halmahera Island, North Maluku, Indonesia, in July 1993. A total of 422 fecal samples were examined by using Kato-Katz thick smear, modified Harada-Mori culture and formalin ether concentration techniques. Seven nematode species, ie Ascaris lumbricoides, Trichuris trichiura, Necator americanus, Ancylostoma duodenale, Strongyloides stercoralis, Enterobius vermicularis and unidentified rhabditoids of free-living nature, were detected. Trematode and cestode infection was not proven. Necator americanus was the predominant species of hookworm. Soil-transmitted nematode infections were highly prevalent. Among the young inhabitants aged less than 15, positive rates of Ascaris, Trichuris and hookworm infections were 32.7, 52.7 and 68.6%, respectively. Among the people aged 15 or more, the positive rate for hookworm (85.9%) was much higher than that for Ascaris and Trichuris (13.5 and 40.5%, respectively). Egg count revealed that more than 90% of inhabitants with Trichuris or hookworm had light infections. The latrines in the surveyed area seemed to have only limited effects on the improvement of the parasitological status because the prevalence of Trichuris infections was much higher in a village where most houses were provided with latrines. These conflicting conditions were considered to have been caused by many factors including the inadequate structure of the latrines.