Objective To investigate the changes in the population density indices of Aedes albopictus and their influential factors in Ningbo city, China, and to provide a basis for the control of dengue vector. Methods The densities of Ae. albopictus larvae in different environments in Ningbo were monitored and investigated, and the relationship between the changes in densities and climate and environment were analyzed. Results The container index (CI), house index (HI), and Breteau index (BI) for Ae. albopictus in Ningbo were 9.26%, 8.88%, and 10.57, respectively, in 2011, and the total density of Ae. albopictus larvae reached the peak value in August. The density in the permanent container was significantly higher than that in the temporary container, with the maximum value in the pool and tank; the density in resident community was significantly higher than that in the park, construction site, and salvage station, with the minimum value in the school and hospital. Conclusion The population density of Ae. albopictus and its seasonal fluctuation were influenced by multiple factors.

Objective To summarize the integrated rodent control measures in large-scale supermarkets by investigation and analysis of the cause of rodent damage therein. Methods The bait and trap methods were employed to capture rats for analysis of rodent palatability, density and population distribution. The powder trace method was used to evaluate the deratization effect. Results Rattus norvegicus was the predominant rodent species in large-scale supermarkets; apples were most palatable to the rats. The positive rate of rodent traces was 36.51% before the implementation of integrated control measures, and dropped to 0 after three months of rodent control, with a deratization effect of 100%. No rodent trace blocks were found in the following three consecutive months. Conclusion The integrated control measures were effective in rodent control.

Objective To investigate the epidemic situation of encephalitis B and vector mosquitoes, and to provide information for its prevention and control. Methods Collecting and analyze epidemic data. Using light trap, scooping larvae to investigate the density of mosquito. Results In 2006, 42 cases of encephalitis B had been diagnosed, 6 of them died. The density index of mosquito of the patient home and other different locations were 6.05 and 13.22 pieces per light per hour, respectively; Culex( Cx.) tritaeniorhychus were 71.44% and 76.01% respectively. At 26 investigated breeding fields surrounding, respectively the larva density index(LDI) was 12.04 individuals per scoop, while Culex pipiens pallens were 49.44%, Cx.tritaeniorhychus were 37.87% of the total number the larva positive rates of container and crock amassing rain were 54.31% and 30.22% respectively. Aedes albopictus were 66.67% and 49.66% respectively; Cx.tritaeniorhychus were 25.11% and 33.42% respectively; Cx.pipiens pallens were 8.22% and 13.62% respectively. Conclusion The main vector of encephalitis B, Cx.tritaeniorhychus is popular in Ningbo. More attention should be paid to accination and mosquito control in encephalitis B control in Ningbo.