Lawa model:

Opisthorchiasis caused by human liver fluke Opisthorchis viverrini infection is a major foodborne parasitic zoonotic diseases in Thailand and neighboring Mekong countries with over 10 million people infected. The infection is associated with cholangitis, cholecystitis, gallstones, hepatomegaly, periductal fibrosis and cholangiocarcinoma (CCA), a fatal liver cancer arising from the bile duct epithelium. The rates of CCA in regions where the parasite is endemic are unprecedented.  Khon Kaen province in Northeast Thailand where O. viverrini is endemic has reported the highest incidence of CCA in the world.  Extensive research on various aspects of opisthorchiasis and its associated diseases has been carried out in Thailand in recent decades. However, current status of O. viverrini infection in the country is approaching 85% prevalence in certain endemic areas even after over 30 years of several rounds of control program.  Its complex life cycle which involves several hosts/environments makes it difficult to control by conventional methods.  Therefore, a new control strategy for liver fluke infection using the EcoHealth/One Health approach was introduced into the Lawa Lake area in Khon Kaen province where the liver fluke is highly endemic.  This program has been carried out for over 7 years using chemotherapy, novel intensive health education methods both in the communities and in schools, ecosystem monitoring and active community participation. As a result, the infection rate in the more than 10 villages surrounding the Lake has declined to more than one half of the average of 60% as estimated by a baseline survey. People in the area gained more knowledge of the liver fluke. Strikingly, the Cyprinid fish species, which are the intermediate host, now show less than 1% prevalence compared to a maximum of 70% during the baseline survey. This liver fluke control programme, now named “Lawa model,” has become recognized nationally and internationally, and is being expanded to other parts of Thailand and neighboring Mekong countries.