4096例华支睾吸虫感染病例分析报告

华支睾吸虫又称肝吸虫，人误食生的或未熟透的含有华支睾吸虫囊蚴的淡水鱼或被含囊蚴的鱼肉污染的食物而感染。我院2001-2004年粪检查出华支睾吸虫感染4906例，现报道如下。     

金乡县集贸市场常见淡水鱼虾华支睾吸虫囊蚴调查

华支睾吸虫属后睾科、支睾吸虫属，俗称肝吸虫病，人体感染是因食生的或未煮熟的含有其囊蚴的第2中间宿主鱼、虾而引起的，沼螺与淡水鱼虾分别是华支睾吸虫的第1、第2中间宿主。132种鱼、3种虾可充当华支睾吸虫的第2宿主。我县于1987年曾对居民肝吸虫患者进行过大面积治疗，并取得了显著的社会效益。为掌握我县居民感染华支睾吸虫的危险因素，     

三种吸虫感染与胆管癌发病关系的研究进展

由华支睾吸虫(Clonorchis sinensis)、麝猫后睾吸虫(Opisthorchis viverrini)和猫后睾吸虫(Opisthorchis fe-lineus)所引起的吸虫病是严重危害人类健康的食源性寄生虫病,在亚洲地区流行较为广泛,人们通过食含有囊蚴的生鱼或虾类而感染。长期且重度感染会造成肝脏机能障碍,如胆结石和胆囊炎等。近年来,越来越多的研究表明这三种吸虫与胆管癌之间存在着病因学联系。本文对他们之间的关系及胆管癌可能的发病机制进行综述。     

嫩江流域齐齐哈尔段犬、猫华支睾吸虫感染情况调查

目的了解嫩江流域齐齐哈尔段保虫宿主犬和猫的华支睾吸虫感染情况,为华支睾吸虫病的防治提供参考依据。方法从嫩江流域齐齐哈尔段周边村庄及河岸边采集犬和猫的粪便,在周边县市的动物屠宰场收集犬的肝脏及胆囊:采用改良加藤法检查犬和猫粪便中华支睾吸虫虫卵的感染情况;采用解剖法检查犬的肝脏及胆囊内华支睾吸虫成虫的感染情况。结果嫩江流域齐齐哈尔段华支睾吸虫保虫宿主粪便虫卵的总感染率为8.00%(4/50),其中犬粪虫卵感染率为8.57%(3/35),猫粪虫卵感染率为6.67%(1/15);解剖法发现华支睾吸虫保虫宿主犬的成虫感染率为5.71%(2/35)。结论嫩江流域齐齐哈尔段为肝吸虫病流行较为严重地区,建议加大查治和健康教育等多种防控措施力度,减少华支睾吸虫病对嫩江流域人民的健康危害。     

安徽省华支睾吸虫病的流行概况及防治对策

华支睾吸虫病又称肝吸虫病,在我国流行至少有2300年以上的历史,是由华支睾吸虫感染引起的人兽共患病。华支睾吸虫病又是一种重要的食源性寄生虫病,人群通过生食或半生食含有华支睾吸虫囊蚴的淡水鱼虾而感染。成虫寄生在人体肝胆管内。引起胆管的一系列病理改变,晚期可发生肝硬化。一些资料不断提示华支睾虫感染与胆管上皮癌、肝细胞癌的发生有一定关系。目前,有数据显示全球华支睾吸虫感染人数大约在3500万,在我国体寄生虫病仍然是重要的公共卫生问题。我国肝吸虫病全国感染人数达到1500万。安徽地处暖温带与亚热带过度地区,气候温暖湿润,江、湖水网纵横,适宜本虫的第一、第二中间宿主以及保虫宿主生存,使人群感染机会增多。加之社会环境的变化。人们追求餐饮时尚,吃生、吃鲜的人不断增多,使安微省华支睾吸虫病的流行有扩大趋重之热。     

虫卵ITS-2序列分析鉴别华支睾吸虫和扇棘单睾吸虫的研究

目的建立以分子生物学技术为基础的华支睾吸虫与扇棘单睾吸虫的ITS-2序列分析鉴别方法。方法在华支睾吸虫流行区采集华支睾吸虫和扇棘单睾吸虫成虫,从成虫虫体分离并收集虫卵。以蛔虫、鞭虫、钩虫、蛲虫做对照虫种,按不同虫种和虫卵数分成5个实验组,各组分别提取DNA,并扩增ITS-2序列,对扩增产物进行测序并作同源性分析以确保为目标片段,根据PCR扩增产物电泳获得的条带判定虫种。结果以华支睾吸虫和扇棘单睾吸虫虫卵DNA为模板的PCR产物电泳图谱分别在400bp、500bp左右各显示一条明显条带;在以两种虫卵DNA混合液为模板的PCR产物中,电泳图谱在400bp左右和500bp左右各显示明显条带。将测序得到的两种核苷酸序列进行Blast比对后,显示与GenBank中相应的华支睾吸虫和扇棘单睾吸虫序列高度同源。混入四种肠道线虫虫卵DNA的PCR产物中,除目的条带外,无其他条带。结论该方法可以对华支睾吸虫及扇棘单睾吸虫虫卵进行鉴别,且结果不受常见四种肠道线虫虫卵干扰,敏感性和特异性较高,可作为两虫种的鉴别检测方法。     

非流行区华枝睾吸虫病1例

<正>华支睾吸虫病(Clonorchiasis),俗称肝吸虫病(liver fluke),是由中华分支睾吸虫寄生在人的肝胆管系统,引起以肝、胆病变为主的一种人兽共患寄生虫病。我院收治1例感染华支睾吸虫病患者,现报告如下。病例摘要患者男,46岁,黑龙江省工人。因"乏力1     

后尾蚴抗原免疫荧光技术检测华支睾吸虫病血清抗体的研究

本研究以华支睾吸虫后尾蚴为抗原,用华支睾吸虫病人和实验动物血清及滤纸于血滴进行IFA,并与以成虫石蜡切片为抗原的IFA检测做了比较,同时还就实验大鼠不同时间血清抗体的变化进行了动态观察。     

华支睾吸虫cDNA文库的构建

目的　构建华支睾吸虫cDNA文库。方法　采集华支睾吸虫阳性鱼 ,分离囊蚴 ,感染实验动物兔 ,解剖兔收集华支睾吸虫成虫虫体。应用“一步法”提取华支睾吸虫总RNA ;经过mRNA纯化、cDNA合成 ,以PcDNA3(Amp +)质粒为载体构建文库。挑取 2 0个克隆进行扩增 ,选择 9个克隆进行DNA序列测定。序列结果与GenBank中相关基因进行比对。结果　获得含有 9 7× 10 5个重组子库容量的华支睾吸虫cDNA文库。其中PC6号克隆基因序列与华支睾吸虫半胱氨酸蛋白酶序列具有 93%的同源性。结论　已构建成华支睾吸虫cDNA文库。     

山东省金乡县华支睾吸虫动物宿主感染调查

华支睾吸虫属后睾科，支睾吸虫属，人体感染是因食生或未煮熟的含有其囊蚴的鱼、虾而引起。淡水螺与淡水鱼、虾分别是华支睾吸虫的第一、二中间宿主，已报告有8种螺、132种鱼和3种虾可充当华支睾吸虫的中间宿主；猫、狗、猪、狐狸、獾等哺乳动物系华支睾吸虫常见的保虫宿主。金乡县曾有华支睾吸虫病流行，1987年后人群感染率大幅下降。为掌握金乡县华支睾吸虫病传播因素，     

Roles of liver fluke infection as risk factor for cholangiocarcinoma

Several factors are known to be associated with risk of cholangiocarcinoma (CCA) and infection with the liver flukes, Opisthorchis viverrini and Clonorchis sinensis, has often been singled out as the leading risk factor in east and southeast Asia. In this review, current knowledge of their biology, life cycle, and pathogenesis of O. viverrini, and its role as a carcinogenic parasite are presented. The trends of age‐specific incidence of liver cancer in Khon Kaen, northeast Thailand are considered and compared with the prevalence profiles of O. viverrini. Potential impacts of the liver fluke control program particularly by mass drug administration (MDA) and public health education in the past and a recent drop of incidence of CCA are discussed in relation to primary prevention and control of this fatal bile duct cancer.     

Discovery of Opisthorchis viverrini metacercariae in freshwater fish in southern Cambodia

Small liver flukes, Clonorchis sinensis and Opisthorchis viverini, are fish-borne trematodes (FBTs) causing significant public health problems in Asia. While C. sinensis is distributing mainly in far east Asia, O. viverini is distributing in Indochina peninsula. Recently, however, the geographical distributions of those small liver flukes were proven to be far wider than expected. Nevertheless, little is known about the epidemiology of small liver flukes in Cambodia. The present study is, therefore, aimed at clarifying the status of small liver fluke infections in various species of freshwater fish in southern Cambodia. A total of 1479 freshwater fish, 1316 (89%) comprised of 20 different species of the cyprinoid family and 163 (11%) belonging to 8 families of non-cyprinoids, were collected during May 2007 and February 2008, and the presence of small liver fluke metacercariae was examined by the compression method. Small liver fluke metacercariae were found in 10 species of cyprinoids with the infection rate ranging 2.1-66.7% and the mean intensity of infection of 1.0-15.0 (range: 1-65). For the speciation, adult worms were obtained by experimental infection in hamsters. The small liver fluke found in this study were identified as Opisthorchis viverrini by the morphological features of adult worms, and this identification was confirmed by partial COI sequencing of the metacercariae.     

Trematode infections: liver and lung flukes

Food-borne trematodiases are an emerging public health problem in Southeast Asia and Latin America and of growing importance for travel clinics in Europe and North America. The disease is caused by chronic infections with liver, lung, and intestinal flukes. This article focuses on the most important liver and lung flukes that parasitize man, namely Clonorchis sinensis, Fasciola gigantica, Fasciola hepatica, Opisthorchis felineus, Opisthorchis viverrini, and Paragonimus spp. The article describes the epidemiology of major liver and lung fluke infections, including current distribution, burden, life cycle, clinical signs and symptoms, diagnostic approaches, and current tools for prevention, treatment, and control.     

Taxonomy and biology of liver flukes

Opisthorchis viverrini is a human liver fluke endemic in Thailand, Lao PDR and Cambodia. Three subspecies of Bithynia siamensis and 18 species of cyprinoid fish are susceptible first and second intermediate hosts, respectively. The differentiation between the adult worm of O. viverrini and that of the closely related species, Opisthorchis felineus and Clonorchis sinensis, is mainly based on the shape and position of the testes and the arrangement of the vitellaria. Eggs of these flukes are morphologically similar and problematic in identification. However, the differentiation between opisthorchid and lecithodendrid eggs is possible. Morphology and biology of each stage are comparatively reviewed. Biological aspects of snail and fish hosts are also included.     

Parasitic infections and hepatic neoplasia

Parasitic infections are highly prevalent in the general population. Detecting a relationship between a parasitic infection and cancer is not an easy task; it requires epidemiological, microbiological and molecular biology techniques. In this article the important mechanisms by which parasitic infections may induce carcinogenesis are reviewed. The association between Schistosoma japonicum, Schistosoma mansoni and hepatocellular carcinoma is covered. The cause-and-effect relationship between the liver flukes Opisthorchis viverrini, Opisthorchis felineus, Clonorchis sinensis, and cholangiocarcinoma is also reviewed. The evidence supporting the role of schistosomes and liver flukes in carcinogenesis is discussed. Finally the importance of the primary prevention of these parasitic infections with oncogenic potentials is emphasized.     

Monoclonal antibodies against Opisthorchis viverrini antigens

Summary Monoclonal antibodies (MoAb) were produced against somatic antigens of adult human liver fluke Opisthorchis viverrini. Earlier studies attached diagnostic potential to an 89–90 kD antigen present in both somatic extracts and in vitro culture supernatants as well as to the abundant 16–17 kD tegumental protein doublet. Mice made excellent immune responses to low dose somatic extract adsorbed onto nitrocellulose or to the 80–95 kD region of SDS gel Western blots. The antigen specificities of hybridomas reactive with somatic antigen by ELISA were determined by radioimmunoprecipitation or immunoblotting. Six MoAb reacted with the desired 16 kD tegumental protein. A 90 kD somatic protein was identified by 9 clones. By indirect immunofluorescence, monoclonals reactive with the 16 kD polypeptide identified the outermost surface of the tegument. The 90 kD antigen was associated with all major muscle systems, most strikingly the crossed subtegumental layers, oral and ventral suckers, pharynx and a thin layer surrounding caeca. The biochemical identity of this muscle-associated antigen is unknown, but it is clearly distinct from the previously identified species-specific 89 kD exoantigen. The 16 kD tegumental protein shares epitopes with a number of related flukes. However, 2 MoAb which react with this protein show no crossreaction.     

Liver fluke‐infested graft used for living‐donor liver transplantation: case report and review of the literature

Clonorchiasis is a cholangiopathy caused by foodborne trematode parasites, also known as liver flukes. Clonorchiasis is endemic in a wide geographical area extending from Eastern Europe to Southeast Asia. Infested hosts may remain asymptomatic for decades and consequently their liver can become available as a graft. To date, 20 liver transplantations with liver fluke‐infested grafts have been reported in the literature. All of them occurred in Asian countries. We, here, report the first case to our knowledge in the Western world of living‐donor liver transplantation (LDLT) with an Opisthorchis felineus‐infested graft, and present a review of the literature. A 6‐month‐old girl with decompensated secondary biliary cirrhosis underwent an LDLT with a left lateral graft infested with O. felineus. After prompt diagnosis and adequate therapy, both donor and recipient had an uneventful postoperative course and long‐term follow‐up. Liver grafts infested with liver flukes do not pose a contraindication to liver donation from deceased or living donors, provided that a correct diagnosis and treatment are performed in a timely fashion.     

Role of gastropods in epidemiology of human parasitic diseases

Pulmonate and prosobranch snails, being necessary hosts for parthenogenetic generations of digenetic trematodes, participate in transmission of all trematodoses important from medical point of view. Role of particular gastropods in epidemiology of these diseases is discussed in details. Invasion of land snails and slugs is mainly passive by eggs containing developed miracidia, while enter of these larvae into snails inhabiting fresh-water environments is usually active. Generations in the snail host between miracidia and cercariae vary considerable, depending upon the fluke species. Generally, the cercaria is produced by the sporocyst or the redia. Cercariae usually actively penetrate out of the infected snail and enter water. Leaving out of account cases of encystation of cercariae in external environment (liver flukes of the family Fasciolidae) and active penetration into the final host (blood flukes of the family Schistosomatidae), encystation of these larvae takes place in the second intermediate host. Cercariae of medically important flukes may develop into metacercariae in tissues of fish (liver flukes - Opisthorchis felineus, Clonorchis sinensis, intestinal flukes--Heterophyes heterophyes, Metagonimus yokogawai, Troglotrema salmincola), as well as in crustaceans (pulmonary flukes of the genus Paragonimus), insects (the bipathogenic liver fluke Dicrocoelium dendriticum and other species of the family Plagiorchiidae incidentally found in man), and gastropods (flukes of the family Echinostomatidae, among them perhaps the best known is the Oriental species--Echinostoma ilocanum). In prevention and control of human trematodoses, especially in endemic foci, elimination of snail hosts is a great importance. Using molluscides may be objectionable from the stadpoint of environmental modification through their toxicity to other organisms. Biological control of snail hosts is more attractive. It includes introduction and management of predators, parasites, or pathogens, and intramolluscan competition. Moreover, certain slugs and terrestrial snails participate in transmission of nematode larval stages, including species known as pathogenic for man - the strongylid nematodes of the genus Angiostrongylus). Such infections may be prevented by abstanding from eating raw or inadequately cooked molluscs in endemic areas.     

Opisthorchiasis in Thailand： Review and current status

Opisthorchiasis caused by Opisthorchis viverrini （Oviverrini） remains a major public health problem in many parts of Southeast Asia including Thailand, Lao PDR, Vietnam and Cambodia. The infection is associated with a number of hepatobUiary diseases, including cholangitis, obstructive jaundice, hepatomegaly, cholecystitis, cholelithiasis and cholangiocarcinoma. The liver fluke infection was induced by eating raw or uncooked fish products that is the tradition and popular in the northeastern and northern region, particularly in rural areas of Thailand. Health education programs to prevent and control opisthorchiasis are still required in high-risk areas.