福建省嗜人按蚊防制效果的评价与监测

Evaluation and surveillance on the effect of control for the Anopheles anthropophagus in Fujian province

目的评价灭蚊效果,监测和清除残存嗜人按蚊,巩固抗疟成果,防止疟疾重新暴发流行。方法对嗜人按蚊分布区实施以2g/m2DDT滞留喷洒和20mg/m2溴氰菊酯浸泡蚊帐灭蚊,开展复查评价防制效果。停止灭蚊后,继续开展媒介和疟疾的监测。以叮人率和人房捕获蚊数计算密度。结果闽北14个嗜人按蚊分布县(市、区)258个分布点已全部完成灭蚊后效果考核,平均每个分布点复查3.18次,浦城县部分点监测30年复查20余次。第一次复查发现,80.01%的分布点嗜人按蚊已被清除,残存嗜人按蚊从灭蚊前人房按蚊的34.1%降至4.02%。经继续实施灭蚊措施,1995年后未再捕及嗜人按蚊。1996停止灭蚊措施后,1996-2007年监测期间复查276村(次),捕获人房按蚊13408只,经鉴定全部为中华按蚊,证明福建省嗜人按蚊已被清除。嗜人按蚊媒介区灭蚊前1980年疟疾发病12921例,发病率44.90/万,发热病人血检疟原虫阳性率为23.00%。实施灭蚊措施后,疟疾流行得到有效控制,1992年发病率降至0.43/万,1990-2007年嗜人按蚊媒介区未再出现疟疾暴发流行,1998年以后未再发现当地感染病人。结论DDT滞留喷洒和溴氢菊酯浸泡蚊帐可有效防制嗜人按蚊,反复查灭清除嗜人按蚊是阻断疟疾流行,巩固抗疟成果,防止疟疾死灰复燃的根本措施。

To survey and eliminate the remaining Anopheles anthropophagus in order to evaluate the effect of eradiation of mosquito and consolidate the efforts to control malaria as well as to prevent the break-out of malaria over again, the spots of distribution of An. anthropophagus was re-investigated and this measure was carried out by 2g/m2 DDT residual spraying and mosquito nets impregnated with 20 mg/m2 deltamethrin. The surviving population was still under surveillance after stop of the mosquito eradiation, and the density of mosquito was measured by the rate of population bitten by mosquitoes and the number of mosquitoes caught in the dwellings. In 14 counties （cities and districts） of the north part of Fujian province with An. anthro- pophagus , 258 distribution spots had completed the surveillance effect of mosquito eradiation in an average rate of 3.18 times of re-examinations on the distribution spots. In some spot, such as in Pucheng county, this kind of surveillance had been undertaken even for more than 20 times during 80 years. During the first time re-investigation, the spots of 80.93% were eradiated in a total of 258 villages, and the rate of the remaining An. anthropophaqgus caught in the dwellings had dropped from 34.1% to 4.02%. After the continuation of the measures for mosquito eradiation, no more An. anthropophagus could be caught in this district since 1995. When the measures of mosquito eradiation were stopped since 1996, all the 13408 anopheles caught during the re-surveillance from 1996 to 2007 were identified to be An. sinensis, indicating that the An. anthropophagus had been com- pletely eradiated in Fujian province. Before the setting up of measures of mosquito eradiation, 12921 cases of malaria had been reported in 1980 with a prevalent rate of 44.90 cases per ten thousand of population and the positive rate of malaria parasites found in the blood of the febrile patients was 23.00%. However, after surveillance of the mosquito eradiation, the prevalence rate of malaria bad dropped to 0.43 cases per ten thousand of population in 1992 and no break-out of malaria due to An. anthropophagus could be found from 1990 to 2007 without any reported case of malaria patient since 1998. From these observation, it is evident that measures with DDT residual spraying and mosquito nets impregnated with deltamethrin can control An. anthropophagus effectively and the repeated surveillance on the mosquito eradiation is proved to be a radical meas ure of blocking epidemic of malaria, consolidating the effect of anti-malaria and preventing the break-out of malaria over again