Prospects and Challenges towards Sustainable Liver Fluke Control

Abstract

© 2017 Elsevier Ltd The liver fluke Opisthorchis viverrini (Ov) is endemic in Southeast Asia where more than 10 million people are estimated to be infected. The infection is associated with several hepatobiliary diseases, including cholangiocarcinoma (CCA). Northeast Thailand is a hotspot for Ov transmission, and, despite extensive public health prevention campaigns led by the government, the prevalence of Ov infection is still high. High infection rates result from cultural and ecological complexities where wet-rice agrarian habitats, centuries-old raw-food culture, and the parasite's complex biology combine to create an ideal transmission arena. Here we review the state of our knowledge regarding the social–ecological determinants underlying Ov transmission. We also describe an integrative research rationale for liver fluke control better aligned with sustainable health development. The distinct socioeconomic, cultural, and environmental history of Northeastern Thailand can provide insights into the intransigence of Ov infection prevalence and disease incidence in the region. Agriculture intensification is associated with significant socioeconomic and ecological changes affecting intermediate hosts, their patterns of abundance and diversity and, in turn, influencing transmission to humans. Recent modeling studies suggest that Ov transmission is seasonal and that control should be practiced seasonally rather than year-round in order to maximize resource utility. A better understanding is needed of how interventions can reduce the consumption of raw fish without discouraging food-sharing behavior that reinforces social coherence, a factor well known to positively influence human health