Evaluating the possible transmission in California of food-borne zoonotic trematode parasites carried by the introduced snail Melanoides tuberculata

点击翻译按钮获取中文摘要

Summary Food‐borne trematodiases are caused by trematode parasites and can involve pathologies ranging from abdominal pain, chronic cough, hepatomegaly, bile duct cancer, or even brain hemorrhage. Almost a billion people around the world are estimated to be at risk of infection. Despite their global importance, food‐borne trematodiases are not typically considered to be a public health issue in the United States. This lack of concern may have previously been justified: trematodes are carried by first intermediate host snails, and the US historically lacked the snail species known to carry injurious human‐infecting trematodes. However, one such host snail, Melanoides tuberculata, has now been introduced and established in the United States. Three of its human‐infecting trematodes have co‐established with the snail. Further, preliminary sampling of southern Californian snails reveals that at least two of these human‐infecting trematodes have been introduced to the western US. The introduction of this snail and some of its parasites calls for an evaluation of the possible emergence of food‐borne zoonotic trematodiases originating from the introduced snail in the United States. The proposed research will involve a systematic survey throughout southern California to quantify the presence of the intermediate host snail at 56 fishing localities, and the presence and abundance of its trematode parasites. Further, at a subset of those localities, the investigation will confirm that the trematode stages directly infectious to humans are, indeed, present in fishes that people catch and eat. Food‐borne trematodiases are not on the radar as a public health concern in the United States, but this work may reveal that they should be. The proposed research will provide the first extensive evaluation in the United States of a public health concern involving the possible emergence of food‐ borne trematodiases originating from trematodes carried by the introduced snail, M. tuberculata. By delineating the extent of this potential public health problem in southern California, this research will (1) provide a foundation for additional epidemiological research in southern California and elsewhere in the nation, and (2) open the door for public and veterinary health agencies to take preventative measures to reduce transmission and to inform clinicians of the possible occurrence of previously unappreciated, and potentially undiagnosed, food‐borne zoonotic trematodiases.