河南省信阳市嗜人按蚊传疟作用研究

目的　调查嗜人按蚊的传疟作用 ,为嗜人按蚊分布区媒介监测和制订合理的防治措施提供依据。　方法　在河南省信阳市二十里河村选择 5个自然村作为观察点 ,采用寄生虫学和昆虫学方法进行调查 ,估算嗜人按蚊的媒介能量和临界叮人率。　结果　 1999年 7～ 8月 ,居民带虫发病率为 7.4% ,原虫率为 2 .0 % ,IFAT抗体阳性率为 8.4%。嗜人按蚊密度组成在人房内占优势 ,平均叮人率为 4.9388/(人 /夜 ) ,人血指数为 0 .785 7,媒介能量为 5 .5 2 96 ,是中华按蚊的 6 .2倍。嗜人按蚊临界叮人率为 0 .2 40 7(人 /夜 ) ,而实际叮人率是它的 2 0倍。结论　嗜人按蚊是当地疟疾传播的主要媒介。提示临界叮人率在媒介监测中具有应用的意义。目的　调查嗜人按蚊的传疟作用 ,为嗜人按蚊分布区媒介监测和制订合理的防治措施提供依据。　方法　在河南省信阳市二十里河村选择 5个自然村作为观察点 ,采用寄生虫学和昆虫学方法进行调查 ,估算嗜人按蚊的媒介能量和临界叮人率。　结果　 1999年 7～ 8月 ,居民带虫发病率为 7.4% ,原虫率为 2 .0 % ,IFAT抗体阳性率为 8.4%。嗜人按蚊密度组成在人房内占优势 ,平均叮人率为 4.9388/ (人 /夜 ) ,人血指数为 0 .785 7,媒介能量为 5 .5 2 96 ,是中华按蚊的 6 .2倍。嗜人按蚊临界叮人率为

The Role of Anopheles anthropophagus in Malaria Transmission in in Xinyang City of Henan Province

OBJECTIVE: To study the role of Anopheles anthropophagus in malaria transmission and transmission threshold so as to provide basis for vector surveillance and malaria control strategy. METHODS: Parasitological and entomological methods were used in the investigation at 5 villages of Xinyang City, Henan Province. RESULTS: From July to August, 1999, 74 febrile cases (10.9% of the total population) were examined. Among them 50 were infected, the incidence in the population of surveyed spots was 7.4%. Active detection was made in another randomly selected two villages and found that the parasite rate in the inhabitants was 2.0%, and the positive rate of IFA was 8.4%. Only vivax malaria was detected. An. anthropophagus and An. sinensis were collected, with An. anthropophagus as the predominant one in human dwellings. The estimated man-biting rate and the human blood index were 4.9388 and 0.7858 respectively. The vectorial capacity of An. anthropophagus was 5.5296. The critical man-biting rate of An. anthropophagus was 0.2407 as calculated by the formula (ma = -rlnP/abPh) according to Macdonald's model. The local man-biting rate was 20 times higher than that of the critical man-biting rate. CONCLUSION: The results demonstrated that An. anthropophagus is the principal vector in malaria transmission in the area. The findings imply that the critical man-biting rate is of practicable importance in vector surveillance.