The first reported cases of canine schistosomiasis mekongi in Cambodia

We have been conducting surveys of schistosomiasis mekongi along the Mekong river in Cambodia since 1997. We attempted to detect canine schistosome infection during the survey in 2000 because dogs were reported to be natural reservoirs of the Mekong schistosome in Lao PDR. A total of 28 canine fecal samples were collected in Kbal Chuor village, Kratie Province and examined for schistosome eggs. One specimen had schistosome eggs (positive rate = 3.6%; egg density = 100/gram stool), which showed characteristics of Schistosoma mekongi. During the 2001 survey, one out of 310 canine stool samples was positive for schistosome eggs (positive rate = 0.32%; egg density = 3,456/gram stool). These are the first confirmed cases of canine schistosomiasis mekongi in Cambodia, which suggests that dogs are animal reservoirs of S. mekongi in the survey area. We further tried to detect S. mekongi in cows, water buffalos, pigs,horses, and field rats in five villages in Kratie Province; no schistosome egg was found in the stools of these animals.