云南省广州管圆线虫病自然疫源地调查

Investigation on epidemic focus of angiostrongyliasis cantonensis in Yunnan Province,China

目的调查云南省是否存在广州管圆线虫病自然疫源地,了解人群感染广州管圆线虫的状况,为云南省防治广州管圆线虫病提供科学依据。方法选择云南省南部5个县,开展广州管圆线虫中间宿主、终末宿主感染调查和动物感染实验;用ELISA法进行人群血清流行病学调查。结果1)分别从软体动物和鼠体肺部检获广州管圆线虫幼虫和成虫,大鼠人工感染成功;2)采集5县人群耳垂滤纸血1 653份,ELISA法测定广州管圆线虫抗体,平均阳性率6.59%(109/1653),学生阳性率8.98%,成人阳性率3.48%,差异有极显著性(P<0.01);男性阳性率5.81%,女性阳性率7.28%,差异无显著性(P>0.05)。结论1)云南省存在广州管圆线虫病的自然疫源地,褐云玛瑙螺和拟阿勇蛞蝓科(未定种)是广州管圆线虫重要的中间宿主,褐家鼠、黄胸鼠是自然终末宿主;2)动物实验证明小鼠、豚鼠和家兔不是广州管圆线虫的适宜终末宿主,SD大鼠可作为广州管圆线虫理想的实验动物模型。

Objective To understand the epidemic situation of angiostrongyliasis cantonensis in Yunnan. Methods The investigation of nature infection condition of intermediate hosts and final hosts of Angiostrongylus cantonensis were carried out in five south Yunnan Province counties, artificial infection of rats with A. cantonensis were observed, and a serologic survey to detect antibodies of A. cantonensis in humen by enzyme linked immunosorbent assay （ELISA） was carried out. Results Larvae and adults of A. cantonensis were obtained from Achatina fulica and mice, and artificial infection experiment was successful. A total of 1 653 specimen of blood were collected and tested, and 6.59%were considered to be seropositive. The positive rates of children and adults were 8.98% and 3.48%, and there was significant difference between them（P〈0.01）. The positive rates of male and female were 5.81% and 7.28%, and there was no significant difference（P〉0.05）. Conclusion The epidemic focus infective of A. cantonensis exists in Yunnan, and Ariophantidae sp. and A. f ulica are important intermediate hosts of A. cantonensis, Rattus novegicus and Rattus flavipec tus are nature final hosts. Guinea pigs and rabbits are not the proper final hosts of A. cantonensis. Rats can be an ideal model of experimental animal of A. cantonensis.