The four villages where O. viverrini infection was endemic in Takaev
and Kandal provinceswere located along tributaries of the Bassak River,
one of the main tributaries of the Mekong. The names of most of these
tributaries, except for the Bassak River, are not found on maps, and
villagers simply call them “Tonle” in Khmer, meaning “the River.” In
the rainy season, the tributaries flood and form a large lake (around N
11°50′ and E 104° 56′ on Google Earth) where freshwater fish are
caught for raw consumption by residents of these four villages.
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