Liver Fluke (Opisthorchis viverrini) in Southeast Asia: Can Transmission be Halted Through Mass Drug Administration? (360G-Wellcome-215919_Z_19_Z)

Transmission of the human-infective and carcinogenic trematode Opisthorchis viverrini is ongoing in Southeast Asia. Despite decades of control, an estimated 10 million people are currently infected in Thailand and Laos. Determining which interventions will be most effective requires an understanding of fundamental epidemiological processes, many of which are poorly understood. Using longitudinal egg-count data and parasite population genomics, I propose to estimate anthelmintic efficacy, rates of reinfection, parasite migration within and between countries, and the role of zoonotic hosts (cats and dogs) on O. viverrini transmission. I will incorporate these processes into a predictive agent-based model which will allow the impact of interventions to be simulated. The model output will be informative to policy makers, and the results communicated to at-risk communities. In particular, I will investigate the impact of repeated mass treatment with praziquantel on parasite transmission, an approach that is currently being used on a large scale globally to control macroparasites. Whole-genome sequencing will be key to investigating O. viverrini population structure, migration rates and parasite relatedness between humans and other zoonotic hosts. Therefore, an improved O. viverrini reference genome will be produced with long-read sequencing, and methods to sequence parasites from non-invasive samples will be developed.