关键词: 三峡库区, 病媒生物, 趋势

Abstract:

Objective　The vectors variation trends before and after impoundment of the Three Gorges Reservoir in Yichang were monitored and analyzed for timely implementation of the countermeasures. Methods　The indoor and outdoor rodent density, mosquito density in residential houses and livestock pens, and species composition of rodents and mosquitoes were determined using the night trap method and the labor hour method. Results　No significant changes were observed in the rodent density after impoundment of the Three Gorges Reservoir in Yichang (t＝0.52, P＞0.05). The annual variation of the rodent density constituted a primary decline followed by an increase. As for the small mammal species composition, the indoor and outdoor dominant species before impoundment were Rattus norvegicus and those of the genus Sorex, accounting for 71.07% and 42.11%, respectively. The dominant species after impoundment, indoor and outdoor, were both R. tanezumi, accounting for 41.67% and 42.86%, respectively. The mosquito density in residential houses did not change significantly after impoundment (t＝1.29, P＞0.05), whereas the mosquito density in livestock pens increased significantly (t＝5.01, P＜0.01). In regard to the mosquito species composition, Anopheles sinensis and Culex pipiens pallens were the dominant species before impoundment in residential houses and livestock pens, respectively, accounting for 38.50% and 34.65%; Armigeres subalbatus and An. sinensis were the dominant species after impoundment, accounting for 37.21% and 23.18%, respectively. Conclusion　The environmental changes due to impoundment of the Three Gorges Reservoir in Yichang had led to the alteration in rodent species composition, in addition to significantly increased mosquito density in livestock pens and altered mosquito species composition. It is suggested that vector  monitoring  should  be  strengthened  to  provide  the  decision?making  basis  for  effective  prevention  and  control  of  the occurrence and prevalence of vector?borne diseases.

Key words: Three Gorges Reservoir, Vector, Trend