Haplorchis infections in intermediate hosts from a clonorchiasis endemic area in Meinung, Taiwan, Republic of China.
Snails and freshwater fish were examined from four ponds in the Meinung township in which Clonorchis sinensis was known to be endemic 18 years ago. No metacercariae were found in 478 Tilapia nilotica, whereas of 451 Ctenopharyngodon idellus examined, 16.2%, 3.3% and 0.9% were found to be infected with Haplorchis pumilio, H. taichui and Clonorchis sinensis, respectively. In addition, there were some unidentified metacercariae in 12.0% of Ctenopharyngodon idellus examined. Overall, no positive correlation between infection rates and sizes of infected fish was shown. Six species of snails were collected in this survey and two frequently-occurring snails, Melanoides tuberculata and Thiara granifera were commonly infected with H. pumilio. Reasons for the prevalence of Haplorchis species and the absence of Clonorchis sinensis in fish and snail hosts in a previously reported endemic area for human clonorchiasis are discussed.
Wang
Jiun-Jye
JJ
Department of Parasitology, Kaohsiung Medical University, Taiwan, Republic of China.
Chung
Lee-Yii
LY
Lee
June-Der
JD
Chang
Eddy-Essen
EE
Chen
Eng-Rin
ER
Chao
David
D
Yen
Chuan-Min
CM
D000818:Animals; D003003:Clonorchiasis / Q000453:epidemiology / Q000662:veterinary; D004197:Disease Reservoirs; D019353:Endemic Diseases; D005393:Fish Diseases / Q000453:epidemiology / Q000469:parasitology*; D005399:Fishes / Q000469:parasitology; D005618:Fresh Water; D006578:Heterophyidae / Q000302:isolation & purification*; D015995:Prevalence; D012908:Snails / Q000469:parasitology*; D013624:Taiwan / Q000453:epidemiology; D014201:Trematode Infections / Q000453:epidemiology / Q000662:veterinary*