The Paragonimus westermani Group in India -Systematics and Genetic Variation

本文以孟加拉虎标本为基础，对Kerbert于1878年所描述的新种“Distoma westermani”进行了澄清，并对发生在印度东北部一些吸虫病流行地区的吸虫病种的系统亲缘关系和生活史进行了研究。1993年9月23日至1993年10月16日期间，在印度东北部的曼尼普尔进行了实地调查。淡水蟹2种共894只；在曼尼普尔邦7个地区的12个地点采集曼尼普尔斑腹蝇678只和长尾蝇216只，进行吸虫感染检查。从manipurenensis和Barytelphusa lugbris中分别分离到了827株和1株。经证实，前者是该地区重要的蟹宿主和人类吸虫感染源。所得的囊蚴初步分为“大型威氏假单胞虫型”、“小型威氏假单胞虫型”、“囊化假单胞虫型”和“异源假单胞虫型”4组。分别检出吸虫401、31、383、13只。他们分别接种到狗、猫和老鼠身上。成年吸虫的形态与Vevers（1923）对westermani虫型的描述一致，但与Kerbert（1878）的描述不一致。目前正在对印度吸虫进行进一步系统的遗传和分子生物学研究。

The present study is to make clear what Paragonimus westermani is which was described by Kerbert in 1878 as a new species, Distoma Westermani on the basis of the specimens from a Bengal tiger, together with the systematic and genetic relations as well as their life histories of Paragonimus species occurring in some endemic areas of paragonimiasis, north-eastern India.During the period of September 23, 1993 - October 16, 1993, the field investigation was carried out in Manipur, north-eastern India. A total of 894 freshwater crabs belonging to two species ; 678 Potamiscus manipurensis and 216 Barytelphusa lugbris were collected from 12 localities of 7 areas in Manipur and examined for Paragonimus infection. Eight hundred and twenty-seven Paragonimus metaceracriae were isolated from P. manipurensis and one was from Barytelphusa lugbris. The former species was proved to be an important crab host and source of human Paragonimus infection in this area. The metacercariae obtained were provisionally classified into 4 groups : "Large P. westermani type", "Small P. westermani type", "Excysted type" and "P. heterotremus type". The number of respective type of Paragonimus metacercariae obtained was as follows : 401, 31, 383 and 13. They were inoculated into dogs, cats and rats, respectively.The morphology of adult flukes, originating from the metacercariae of Large and Small P. westermani types was in good agreement with the description of P. westermani by Vevers(1923), but not by Kerbert(1878).Further systematic, genetic and molecular biological studies on Indian Paragonimus are now in progress.