福建省浦城县东方次睾吸虫感染及疫源地的调查

Epidemiological investigation on Metorchis orientalis infection in endemic villages in Pucheng County, Fujian Province

为了解福建省南平市浦城县人群及动物宿主的东方次睾吸虫感染情况,于2016-2017年随机抽取富岭镇瑞安村、临江镇水东村、水北街曹村村、仙阳镇管九村、万安乡连墩村等5个调查点,采用改良加藤厚涂片法检查3岁以上人群粪样中东方次睾吸虫虫卵感染情况。在水东村和管九村居民住房周围的2个鱼塘捕捞野生淡水鱼类,取鱼体尾鳍及背鳍部肌肉,以压片法观察囊蚴感染情况。购买家鸭,取胆囊,另收集市售肉鸭丢弃的胆囊,检查并鉴定检获的虫体。采集野外家猫、家犬等粪便,以水洗沉淀法检查虫卵。取捕捞的麦穗鱼30尾,分别喂养2只雏鸭各15尾, 1个月后取鸭肝、胆,收集虫体,卡红染色后鉴定虫种。结果共调查1 168人,检出东方次睾吸虫虫卵感染7例,感染检出率为0.6%。男性感染者4例,女性3例;年龄为24～83岁。捕捞的淡水鱼共5种340尾,其中检出囊蚴感染190尾,感染检出率为60.1%。以麦穗鱼感染检出率为最高,达90.3%(177/196),平均每尾鱼感染囊蚴62个。检查家鸭15只,胆囊感染囊蚴4只;检查市售肉鸭胆囊50份,未检出阳性者。检查猫粪14份,感染1份;检查犬粪30份,感染1份。喂养麦穗鱼的2只家鸭,其肝、胆中检获10条东方次睾吸虫。提示浦城县人群、动物、淡水鱼类均有东方次睾吸虫感染。

In order to investigate the endemic status of Metorchis orientalis infection in human, mammals, poultries and fishes, an epidemiological survey was performed in randomly selected 5 endemic villages in Pucheng County during 2016-2017. The modified Kato-Katz thick smear method was applied to examine eggs in fecal samples of villagers with over 3-years old. Fresh water fishes were collected from two ponds around villages of Shuidong and Guanjiu and metacercariae were examined in their muscle. The gallbladders were collected from ducks purchased from local market or from dumped wastes and the adult worms were collected and counted. Fecal samples were also collected from cats and dogs and eggs were examined by precipitation concentration and microscopy. Two ducks were each fed with 15 fish (Pseudorasbora parva). The adult worms were collected from gallbladders of the infected ducks and stained with carmine red. Seven people were found infected with M. orientalis from 1 168 subjects examined. The human infection rate in these villagers was 0.6%, 4 of them are males and 3 females with age ranged from 24-83. 190 metacercariae were identified in 340 collected fishes which belonged to 5 species. The infection rate in fish was 60.1% and the P. parva had the highest infection rate of 90.3% (177/196) with average 62 metacercariae infected. 4 out of 15 home-raised ducks were infected and adult worms were identified in their gallbladders. No infection was identified in total examined 50 gallbladders from ducks sold in the market. One each from 14 cat fecal samples and 30 dog fecal samples were infected with M. orientalis. Ten adult worms were collected from two ducks experimentally infected with metacercariae-infested P. parva. The epidemiological survey demonstrated that M. orientalis is endemic in Pucheng County, which infects human, mammals, ducks and fresh water fishes.