Clonorchis sinensis metacercarial infection in the pond smelt Hypomesus olidus and the minnow Zacco platypus collected from the Soyang and Daechung Lakes

Abstract

Various species of freshwater fish are known to be the second intermediate hosts for Clonorchis sinensis (Ide, 1935;Joo, 1988;Sohn and Choi, 1997;Nam and Sohn, 2000). The pond smelt Hypomesus olidus and the minnow Zacco platypus are small freshwater fish, and popular for ice-fishing during the winter season in the Republic of Korea; they actively strut in water during winter, but remain in deep water during the other seasons. Without verification, people simply thought that these fish, particularly the pond smelts, would be free from parasitic infections, since they have a clean, translucent body and live in clear, uncontaminated water. There have been newspaper reports that people enjoy catching these fish at ice-fishing festivals during the winter and eat them uncooked.However, a paper in Japan (Ide, 1935), and another in the Republic of Korea (Nam and Sohn, 2000), have reported the role of the pond smelts as a second inter- Department of Parasitology and Tropical Medicine, Seoul National University College of Medicine, and Institute of Endemic Diseases, Seoul National University Medical Research Center, Seoul 110-799,2) Department of Parasitology and Institute of Malariology, Inje University College of Medicine, Busan 614-735, KoreaAbstract: The pond smelt Hypomesus olidus and minnow Zacco platypus were collected from the Soyang and Daechung Lakes in January 2003, and their metacercarial infections was examined by the muscle compression and artificial digestion techniques. In the Soyang Lake, 161 metacercariae of Clonorchis sinensis (0.35 per fish) were harvested from 459 pond smelts examined. Also, 13 metacercariae of C. sinensis (0.43 per fish), 1 of Metagonimus sp., 4 of Echinostoma sp., 148 of Centrocestus armatus and 44 unidentified species were collected from 30 minnows. In the Daechung Lake, 369 metacercariae of C. sinensis (3.69 per fish) and 51 unidentified species were recovered from 100 pond smelts. The metacercariae of C. sinensis were fed to experimental rats, in which the adult flukes were identified. The pond smelts and minnows collected from the Soyang and Daechung Lakes were verified to be the second intermediate hosts and the sources of human C. sinensis infection.

Infection Status of Freshwater Fish with Metacercariae of Clonorchis sinensis in Korea

“…Up to present, 3 studies have investigated infection status of pond smelts by metacercariae of C. sinensis [2][3][4]. Two studies examined hundreds of the fish by one batch of artificial digestion, and one reported positive results of the fish from Taehoman in 1998 and Soyangho in 1999.…”

“…Of these, Pseudorasbora parva, Pungtungia herzi, Pseudogobio esocinus, Sarcocheilichthys sinensis, and Hemibarbus labeo were confirmed as major intermediate hosts of C. sinensis in Korea. Recently, the pond smelt, Hypomesus olidus, became a newly recognized intermediate host of C. sinensis [2][3][4]. The pond smelt is a favorite freshwater fish which many people eat alive during winter.…”

Research Note. Prevalence, protein analysis and possible preventive measures against zoonotic anisakid larvae isolated from marine Atherina fish

“…This study put forward the claim that this protein is considered a potent allergen released from the excretory gland of anisakid larvae (Moneo, 2000). The gene coding for this protein was isolated from A. simplex L3 cDNA library by expressed sequence tag analysis (Park et al, 2004). Other study reported several protein bands of A. simplex larvae with molecular weights of 43.90, 35.14, 32.18, 27.85, 25.60, 20.10, 18.78, 18.10, 17, 15.20 and 14.30 KDa (Amany, 2007).…”

“…This is due to the fact that the excretory/secretory products (ESPs) of anisakid larvae are recognized by the host as foreign antigens (Raybourne et al, 1986). These proteins might invoke gastro-allergic symptoms and sensitivity in infected human (Moneo et al, 2005;Park et al, 2011;Park et al, 2012;Cho & Lee, 2006). A number of anisakid proteins have been recognized and listed in the Allergome database (Mari et al, 2009;Cho et al, 2014).…”

“…In this method, the viscera and muscles of the collected marine Atherina were compressed between two glass slides and examined under a dissecting microscope (Park et al, 2004).…”