PREVALENCE OF INTESTINAL PARASITE INFECTION IN TOUL ROKA VILLAGE, PHNOM PENH MUNICIPALITY CAMBODIA

Intestinal parasitic infection is a serious public health problem among the inhabitants in developing countries located in tropical areas. Control activities of parasitic diseases are not only an important health improvement problem in a given area but also an entry point for effective public health care activities because of its serious prevalence among inhabitants and its nature as an environment-derived disease (Fereydoun, 1984) . Also, intestinal helminthiasis can be easily diagnosed with fecal samples and are treatable by oral administration of anthelmintics; it can be performed intensively as an ordinary public health care activity. Additionally, intestinal parasitic infection occurs closely relating to the environmental sanitary condition; parasite control program may relate directly to the education for improvement of sanitary condition. Exact survey on the prevalence of intestinal parasite infection may also be important to know health status of the inhabitants in a given area. Due to the civil war for a long period in Cambodia, the information on the recent prevalence of intestinal parasites is extremely few. In the country, Cambodia-Okinawa Friendship Association (COFA) , founded in 1992 as a non-government organization (NGO) in Okinawa, has established a clinic in a village, Toul Roka Village, to contribute to health care of the villagers and started a parasite control program since 1998. The present study was undertaken to obtain basic information on the recent prevalence of intestinal parasitic infection among the inhabitants in the village. Although the village is located in suburban area of Phnom Penh Municipality, the general socio-economic and sanitary conditions were consistently poor in the village. A total of 457 villagers live in 61 households in the village. The survey was conducted by stool examination in December, 1998. For stool examination, the authors visited all households to explain the purpose of the survey and delivered stool containers to all families. After delivering the containers, stool samples were collected and examined both by Kato-Katz thick smear method (Kato and Miura, 1954) and formalin-ether concentration method (Ritchie, 1948) . Their life habits were also surveyed by the interview to the representative adults of each family. In the present preliminary study, stool samples from 113 villagers, accounting for 24.7% of the population subjected, were collected randomly for examination. Table 1 represents the results of the stool examinations. A total of 7 helminth and 9 protozoan species were diagnosed in 80.5% of the villagers examined. Sixtyseven samples (59.3%) were found harboring one or more helminth infections. Among the helminth species, Ascaris lumbricoides was the commonest parasite, showing 48.7% of prevalence rate. Hookworm infection was also demonstrated in 15.9% of the villagers. On the other hand, Trichuris trichiura infection was rare among the villagers, although their infection mode is almost the same to that of A. lumbricoides. Interestingly, the infection rate with Opisthorchis viverrini, liver fluke, were only 3.5% (4 cases) , in spite of frequent eating of raw fishes by the villagers. When the prevalence rates were compared between age groups divided by 15 years old, the infection rate of A. lumbricoides was higher in the younger age population, but it was reversed by the aged group over 15 years old in the case of hookworm infection. As to protozoan parasites, 9 species of protozoan parasite were detected in 61 (54.0%) villagers. The commonest species was Blastcystis hominis, showing positive rates of 37-43%. Entamoeba histolytica/ E.