不同生态环境中螺广州管圆线虫感染率的调查

Investigation on the Infection Rate of Angiostrongylus cantonensis in Snails from Different Ecological Environments

目的了解采自罗湖区不同生态环境中福寿螺、褐云玛瑙螺及市售中华圆田螺广州管圆线虫感染率的情况,为广州管圆线虫病防治及食品安全提供科学依据。方法市场购买50个中华圆田螺,在水池、小溪各采集50个福寿螺,在灌木丛、草莓地和住宅小区各采集45只褐云玛瑙螺。将每只螺制成组织匀浆,用显微镜检查广州管圆线虫三期幼虫,比较不同种类及区域螺类感染率的差异。结果本地福寿螺、褐云玛瑙螺与外地产的中华圆田螺平均感染率分别是30.0%、15.6%和8.0%,差异有统计学意义(χ2=14.05,P<0.05)。本地水池与小溪的福寿螺感染率分别是56.0%、4.0%,差异有统计学意义(χ2=32.2,P<0.001)。灌木丛、草莓地和住宅小区褐云玛瑙螺感染率分别是31.1%、11.1%、4.4%,差异有统计学意义(χ2=14.5,P<0.05)。重量在27.8 g以下或以上的褐云玛瑙螺的感染率分别为11.76%和19.40%,感染率差异无统计学意义(χ2=1.5,P>0.05)。重量为10.75 g以下和以上感染率分别为24.00%和36.00%,感染率差异无统计学意义(χ2=1.7,P>0.05)。结论深圳市罗湖区福寿螺感染率高于褐云玛瑙螺,水池中福寿螺的感染率高于溪流,螺的感染率与其重量未见相关,市售中华圆田螺也有广州管圆线虫感染。

Objective To investigate the infection rates of Angiostrongylus cantonensis in Pomacea canaliculata and Achatina fulica from different ecological environments and in Cipangopaludina cahayensis for sale,so as to provide scientific basis for angiostrongyliasis prevention and food safety.Methods Fifty Cipangopaludina cahayensis were purchased in the Guandong Dongmen Market.Fifty Pomacea canaliculata were collected from the sewage pool and the creek respectively,and 45 Achatina fulica were collected from the shrub,the strawberry field and the residential area respectively.The third phase larvae of Angiostrongylus cantonensis in the well-proportioned tissue solution made from each snail were observed under the microscope.The infection rates were compared by chi-square test among different snail species and regions.Results The infection rates of Angiostrongylus cantonensis in the local Pomacea canaliculata,local Achatina fulica and ecdemic Cipangopaludina cahayensis were 30.0%,15.6% and 8.0% respectively,indicating significant difference（P0.05）.The infection rates in the Pomacea canaliculata from the sewage pool and the creek near the Quishui mountain were 56.0% and 4.0%,respectively,with statistical difference（P0.001）.The infection rates for the Achatina fulica collected from the shrub,the strawberry field and the residential area were 31.1%,11.1% and 4.4% respectively,which were statistically different（P0.05）.The infection rates for the Achatina fulica with weight lower or higher than 27.8g were 11.76% and 19.40% respectively,and did not reveal any significant difference（P0.05）.Neither did the infection rates for the Pomacea canaliculata with weight lower or higher than 10.75g（36.00%,24.00% respectively,P0.05）.Conclusions The infection rate of Angiostrongylus cantonensis in the Pomacea canaliculata is higher than that in the Achatina fulica in Luohu District,Shenzhen.The infection rate in the Pomacea canaliculata from the sewage pool is higher than that from the rivulet.The infection rate in the Achatina fulic from shrub is higher than that from the strawberry field and the residential district.The infection rate in the snails does not correlate with their weight.Infection of Angiostrongylus cantonensis is also found in the Cipangopaludina cahayensis for sale.