Control Measure of Fishborne Zoonotic Trematodes: A Review

Fishborne zoonotic trematodes (FZT) were classified into small intestinal, lung, and liver flukes. Some species of the family Heterophyidae, Echinostomatidae, Clinostomidae, and Diplostomidae which considered to be fishborne zoonotic intestinal flukes infect the health of both fish and humans. Some species of the family Heterophyidae parasitize fish and cause diseases to humans when eating them. Symptoms are differed in patients with echinostomiasis, including anemia, stomach ache, headache, and loose stools. In heavy infections, there are other symptoms such as profuse watery diarrhea, easy fatigue, eosinophilia, edema, loss of body weight, and anorexia. Meanwhile, the important symptoms of Clinostomidae digenetic trematode are Yellow grub disease which is transmitted to humans via ingestion of raw or inappropriately cooked fish leading to Halazoun-like disease “laryngopharyngitis” that can cause death from asphyxiation. There are variable processing methods that can control in human disease by encysted metacercariae (EMC) such as grilling, frying, heating and cooking, boiling, freezing, and chilling. Grilling of some infected fish with EMC for 5-20 minutes at 60-80˚C and 90 °C for at least 5 min was sufficient to destroy the EMC. Frying for 10 minutes killed all EMC too. Heating for 15 min at 60 °C, 100 °C, and 180 °C can destroy all metacercariae. Cooking at 250°C for 15-20 min can decrease the viability of EMC. The complete destruction of EMC occurred after chilling at 4 °C for above 24 and over 48 hours. Freezing at -4C° to -5C° for 10 days will keep the fish completely safe for consumers.