O.<unk>  remains a major public health problem in the Mekong Basin in Southeast Asia. It is endemic in Thailand, the Lao People's Democratic Republic, Vietnam, and Cambodia.It is most prevalent in Thailand, and for this reason Thailand has the highest incident of<unk> sis-associated cancer, cholangiocarcinoma (CCA) in the world. About 9.6% of the total population of Thailand is estimated to be infected. It is most abundant in northern Thailand, while it occurs moderately in central Thailand. According to the five-year national survey from 2010 to 2015, the highest incidences reached up to 45.7% of the population in northern Thailand. However, there is no record of<unk> sis due to O.<unk>  in southern Thailand. School children are most infected, and the infection was very high before 1984, after which there was mass treatment programme, and the prevalence sharply declined after 1994. A national survey in Lao PDR (under the project of Korea-Laos Collaborative Project for Control of Foodborne Trematode Infections in Lao PDR) between 2007 and 2011 indicates that it is the most prevalent helminth infection, amounting to 55.6% of the infection. It is not highly prevalent in Vietnam, but accurate survey is difficult because it is often co-infected with other flukes such as Haplorchis pumilio, H. taichui, and C. sinensis. It is most abundant in the northern provinces. It is least prevalent in Cambodia. A national survey between 2006 and 2011 showed that it is the second most prevalent helminth accounting for 5.7% of the total infection, after hookworm with 9.6% of the infection.
Opisthorchis viverrini
Echinostoma cinetorchis
Opisthorchis felineus
Schistosoma japonicum
Haplorchis taichui
Taenia asiatica
Taenia solium
Echinostoma revolutum