福建省龙海市广州管圆线虫贝类宿主种群生态及感染率调查研究

Population ecology of medical shellfish and the infection rate of Angiostrongylus cantonensis in Longhai City,Fujian Province,China

目的调查龙海市医学贝类种群及其广州管圆线虫感染率。方法按不同类型孳生地设调查点,采集水生和陆生贝类。用肺检法检查大瓶螺肺囊,其他贝类用捣碎匀浆法,检查广州管圆线虫Ⅲ期幼虫。比较匀浆法和肺检法在褐云玛瑙螺体组织的检查效果。调查影响贝类感染率的生态环境因素。结果调查9个乡镇27个调查点1 673份标本,查出大瓶螺、石环棱螺、铜锈环棱螺、瘤拟黑螺、褐云玛瑙螺、高突足襞蛞蝓、双线嗜粘液蛞蝓和同型巴蜗牛等8种贝类,广州管圆线虫总感染率为19.78%。其中高突足襞蛞蝓最高,达56.63%(47/83),褐云玛瑙螺和大瓶螺分别为39.32%(92/234)与27.14%(130/234)。各调查点感染率高低与其距离居民生活区远近密切相关。首次在瘤拟黑螺内检及广州管圆线虫幼虫。肺检法和匀浆法的检出率分别为87.1%与100.0%,两者差异有统计学意义。结论高突足襞蛞蝓、褐云玛瑙螺和大瓶螺为当地感染广州管圆线虫优势种群,感染率同各种贝类的微生态环境关系密切。瘤拟黑螺充当广州管圆线虫新宿主。肺检法不适合用于褐云玛瑙螺的的广州管圆线虫感染定性筛查。

The aim of the study was to investigate the population ecology of medical shellfish and the infection of An-giostrongylus cantonensis in Longhai ,Fujian Province ,China .Aquatic and terrestrial shellfish were collected in survey points according to different types of breeding grounds .Then ,lung-microscopy method was involved in the detection of the lung tis-sue in Ampullaria gigas .Other shellfishes were mashed to detect the third-stage larvae of Angiostrongylus cantonensis .Hom-ogenization and lung microscopy were compared in the detection of the larvae of A .cantonensis in Achatina snails .Factors re-lated to the environment and influence of shellfish hosts were also included .Results showed that 8 species of molluscans were found ,including Pila gigas ,Bellamya aeruginosa ,Bellamya lithophaga ,Melanoides tuberculata ,Achatina fulica ,Vag-inulus alte ,Philomycus bilineatus ,and Bradybaenasimilaris with 1 673 specimens in 27 survey points from 9 townships .The infectionratewas19.78% inaverage.TheinfectionrateinV.altewas56.63% （47/83）;theinfectionratesforA.fulicaand P .gigas were 39 .32% （92/234） and 27 .14% （130/234） ,respectively .The infection rate of each survey point was closely re-lated to the distances from the residents living area .Morever ,A .cantonensis larvae were detected in M .tuberculata .Lung mi-croscopy and homogenization method detection rate was 87 .1%and 100 .0% ,respectively .The difference was statistically sig-nificant .In conclusion ,V .alte ,A . fulica and P .gigas were A . cantonensist infection dominant population . The infection rate was closely related to micro-ecological environment for all kinds of shellfish .M .tuberculata was the new host of A .can-tonensis .Lung microscopy method should not be used in the qualitative screening detection of A . f ulica infected with A .can-tonensist .