Schistosomiasis in Cambodia: a review.

Human schistosomiasis has been known in Cambodia only since 1968. In 1968-1970, many cases were detected in the provincial capital of Kratié. Infection seemed to be confined to the ethnic Vietnamese fishermen who inhabited raft houses (= floating villages) on the Mekong River at Kratié. Overall prevalence in fishermen of all ages was between 7 and 10%. In the children of fishermen between the ages of 1 to 14, the prevalence was between 14 and 22%. Transmission was apparently limited to floating houses stationed more or less permanently near shore and connected to each other in a chain. It is believed that transmission occurred only in the areas of still water which were created between raft and shore. The principal focus of schistosomiasis in Cambodia appears to be Kratié. Only a few cases have been detected elsewhere in the country. The parasite is undoubtedly identical with the Schistosoma reported from humans and dogs at Khong Island, Laos. However, the transmitting snail in Laos, Lithoglyphopsis aperta, has thus far not been reported from the Mekong River in Cambodia.

Mekong schistosomiasis. 4. A parasitological survey of wild rodents, domestic pigs and cattle on Khong Island, Laos.

No evidence of infection with the Mekong Schistosoma was found in 12 Rattus exulans, 81 R. r. molliculus, and 10 Bandicota savilei caught in the vicinity of and downstream from the schistosomiasis transmission focus on Khong Island, South Laos, and examined by dissection and portal perfusion. Likewise, no eggs of the Mekong Schistosoma were detected in faeces of 15 domestic pigs or 43 domestic cattle examined on Khong Island both by merthiolate-iodine-formalin concentration and by the hatching technique. These results suggested that the wild rodents listed above, as well as pigs and cattle in the vicinity of Khong Town, may not contribute significantly to the transmission of the Mekong Schistosoma under present conditions.