Analysis of surveillance results of dengue fever in Sichuan province

Objective To investigate the distribution of the vector mosquito of Dengue,Aedes albopictus,in Sichuan province,providing data for the prevention and control of dengue fever. Methods The larval index and adult densities of Ae. albopictus in its breeding grounds were monitored at ten representative observation spots by specified technicians. Results The container index was 27.50% at the ten monitoring spots,the overall adult mosquito density 8.08 per man-hour. The highest container index,60.28%,was observed in discarded tires. Relatively higher densities of mosquitoes were found at special places and breeding and farming areas,being 18.17 and 10.08 per man-hour,respectively. The density was also high in summer,reaching a peak of 9.79 per man-hour. Regional variations in population densities of Ae. albopictus were observed,yet without geographic variations. The larval and adult density were correlated to a certain extent at various monitoring spots. Conclusion Ae. albopictus is widely distributed in Sichuan province,and may result in outbreaks of Dengue in case of imported cases. Therefore,we should strengthen surveillance of mosquito vectors.