Parasitic diseases with emphasis on schistosomiasis in Cambodian refugees, in Prachinburi Province Thailand.

Epidemiologic surveys were carried on 24,619 Cambodian refugees in Khao-I-Dang holding center, employing a skin test as a screening device to determine the prevalence of schistosomiasis. The diagnosis of Schistosoma mekongi was confirmed in 62 by positive stool examination. The majority of the positive cases came from Battambang province which is probably a new endemic area of schistosomiasis in Cambodia.

Freshwater snails survey in and around the Cambodian refugee camp, Sakaeo District, Prachinburi Province, Thailand.

The freshwater snails surveys were carried out during September 15, 1981 to December 15, 1981, especially for the intermediate or possible intermediate host of Schistosoma mekongi in and around the Cambodian refugee camp at Ban Kaeng Holding Centre, Sakaeo District, Prachinburi Province. A total of 30 localities were visited and 15 species of freshwater snails were collected. The snails did not shed any cercaria of S. mekongi and none of these was the intermediate host of S. mekongi.

Schistosomiasis in Cambodian refugees at Ban-Kaeng Holding Centre, Prachinburi province, Thailand.

The epidemiologic investigation on schistosomiasis in 21,496 Cambodian refugees residing at Ban-Kaeng Holding Centre was conducted by using the skin sensitivity test as a screening test. A positive diagnosis of Schistosoma mekongi was confirmed in 74 of these cases through ova recovery in the stool. The resultant prevalence of schistosomiasis in Ban-Kaeng refugee Holding Center was 3.44 cases per 1,000 population. All of positive cases came from areas in Cambodia where schistosomiasis has not been previously reported. Sixty out of 74 schistosomiasis cases were from Battambang province in Cambodia. This study indicates that schistosomiasis in Cambodia at present is more widespread than has previously been reported.

A survey on intestinal parasitic infections in Laotian refugees at Ubon Province, Northeastern Thailand, with special reference to schistosomiasis.

454 stool specimens were collected from the Laotian refugees residing in the refugee camp, Ubon Province, from August 8 to 11, 1978, and were examined by formalin ether sedimentation technique. One of them (0.22%) was infected with Schistosoma mekongi. Since there are freshwater hydrobiid snails, Lithoglyphopsis aperta, the intermediate host of S. mekongi in that area, it is probable that the disease may become established in Northeastern Thailand in the future, which will eventually lead to health and economic problems in Thailand.

Epidemiology of hookworm infection in Soong nern district, Korat province, Thailand.

Stool surveys in Soong Nern district, Korat Province, were done by the MF concentration technique. The intensity of hookworm infection, egg counts, results of treatment by anthelminthic drugs, observations on new infections and reinfections following treatment throughout the year and the density of nematode larvae in soil in the study area were investigated. Hookworm infection rates were high in Na-Glang village, both in adult villagers and school-aged children. The intensity of hookworm infections was considered mild and after treatment the numbers of eggs in the stools diminished or disappeared. New cases and reinfection increased during the rainy month, due to socio-environmental factors in the village that favoured the development of hookworm larvai in the soil. Although in this study it was impossible to distinguish hookworm larvae among the nematode larvae collected form soil it was highly probable that hookworm larvae were present. Control of hookworm infection in the study area was proposed by improvement of environmental sanitation and health education.