Intestinal Parasitic Infections among Inhabitants of the North, West-central and Eastern Border Areas of Thailand

Abstracts After the 8th Health Development Plan in the year 2001, the Ministry of Public Health, Thailand,reported that the prevalence rate of liver fluke infection was 9.6%, and hookworm infection 11.4%.The data were collected from 30 sample clusters in each of 12 public health regions, but remote areas alongthe border were excluded. Mountainous areas in tropical zones are favorable for the transmission ofparasitic diseases; populations inhabitating the mountains along border areas may harbor several kinds ofparasites. Since population migration in these areas is common, disease transmission from place to place ispossible and may affect the Intestinal Helminthiasis Control Program of the country. In this study, theprevalence of intestinal parasites among populations located along the borders between Thailand-Laos(Nan Province); Thailand-Myanmar (Kanchanaburi Province) and Thailand-Cambodia (Sakaeo Province)were investigated. Stool examinations by Modified Kato-Katz technique revealed that the prevalence ratesof helminthic infection of 55.8% in Nan, 49.4% in Kanchanaburi, and 49.5% in Sakaeo.The species of helminths found in these areas were Necator americanus, Ascaris lumbricoides, Trichuristrichiura, Strongyloides stercoralis, Enterobius vermicularis, Hymenolepis nana, Opisthorchis viverrini, Haplorchistaichui, Taenia saginata, T. solium, and Paragonimus sp. The hookworm infection rates in Nan andKanchanaburi were 25.5% and 46.2%, respectively. In Nan Province, 15.4% of the hookworm cases werein heavy and moderate, while 49.7% of ascariasis cases were classified as heavy and moderate. In Sakaeo,most of the infected population harbored liver fluke (47.9%). It was proved that in the northern borderarea (Nan Province), the small trematode eggs found in stool samples belonged to the minute intestinalfluke, Haplorchis taichui. One case of paragonimiasis was found in a girl from Nan Province. Many cases oftaeniasis were also detected by stool examination.Intestinal protozoa rates among the populations in Nan, Kanchanaburi, and Sakaeo were 30.8, 47.7and 38.5%, respectively. Infections of Blastocystis hominis, Entamoeba coli, Giardia intestinalis, and Entamoebahistolytica were common among villagers near the borders, and some rare species of protozoa were observedamong them, such as Cyclospora cayetanensis, Chilomastix mesnili and Sarcocystis hominis.Controlling parasitic infections among people residing along the borders is rather difficult. The mosteffective method is to give health education to the community via health personnel, health volunteersand teachers, after drug administration. At school, health education programs to prevent disease must beemphasized regularly, to improve personal hygiene and community sanitation in the villages.