Monsters in our food: Foodborne trematodiasis in the Philippines and beyond

Abstract

Foodborne trematodiasis is a neglected tropical disease (NTD) caused by zoonotic trematodes that persist mainly in impoverished areas in the Asia-Pacific region. Globally, about 2 million disability life years (DALYs) are lost due to these parasitic infections. Four groups of foodborne trematodes are known to cause significant illness: fish-borne liver fluke infections caused by Opisthorchis and Clonorchis spp.; water vegetable-borne Fasciola spp. infections; crustacean-vectored paragonimiasis; and those caused by intestinal trematodes. In the Philippines, endemic foodborne trematodes of public health concern include Paragonimus westermani, some members of Heterophyidae and Echinostomatidae, and Fasciola hepatica/ F. gigantica. Opisthorchis viverrini and Clonorchis sinensis have also been reported in the country. Data on the epidemiology of these zoonotic illnesses remain scarce and in need of research attention in the Philippines. Culturally rooted eating behaviors in endemic areas are important risk factors to acquiring and perpetuating foodborne trematodiasis. The combination of mass drug administration (MDA), provision of clean water and maintenance of good sanitation and hygiene (WASH), community health education towards modification of risky behaviors, surveillance, and veterinary public health interventions have been shown to be effective in combatting these zoonotic parasitoses. An integrated control and prevention program anchored on the One Health paradigm is a must to address these illnesses. This paper aims to review the biology and epidemiology of, and public health interventions against zoonotic foodborne trematodiasis in the Philippines and its neighboring countries.