成都市中华按蚊在疟疾传播中的阈值

目的研究成都市中华按蚊传播疟疾的阈值和潜势,为当地疟疾监测、预警与防治提供科学评价指标。方法选取蚊密度较高的4个村为调查点,其中坝区2个、浅丘1个、深丘1个。于2011-07/09现场调查媒介按蚊的叮人率、经产蚊比例、人血指数,收集观察期间的平均气温数据。根据基本繁殖率概念计算以媒介按蚊临界叮人率为指标的传播疟疾阈值。结果成都市中华按蚊的人血指数是0.05,实际叮人率为1.20,中华按蚊对恶性疟和间日疟的临界叮人率分别是12.838 4（恶性疟）和10.553 5（间日疟）。结论成都市按蚊的实际叮人率低于其传播疟疾的临界叮人率,由中华按蚊引起的疟疾传播已被阻断。

Threshold Density of An. Sinensis for Transmission of Malaria in Chengdu

Objective To study the threshold density of An. sinensis in transmission of malaria in Chengdu and provide scientific indicators for the disease surveillance, early warning, prevention and control.Methods From July to September of 2011,field investigation on vectors and malaria surveillance were conducted in 4 villages,2 of which were in plain,one in shallow hill area and one in deep hill area.The entomological investigations included the man- biting rate, the proportion of parous anophelines,the human blood index,as well as data on the mean temperature in the area. Based on the formula of basic reproductive rate,the critical human-biting rate was estimated. Results The human blood index for An. sinensis was 0.05 and the adjusted human-biting rate for An. sinensis was 1.20.The critical human-biting rate was 12.8384 and 10.5535 for Plasmodium falciparum malaria and Plasmodium vivax malaria separately. Conclusion Malaria transmission by this vector in the study area has been interrupted,for that the adjusted human-biting rate of An. Sinensis is lower than the critical human-biting rate of An. Sinensis.