Aedes surveillance in key provinces in southern China, January-February 2017

Objective To analyze the surveillance data of Aedes in 2 provinces in southern China during January-February in 2017 and provide the scientific evidence for the prevention and control of dengue fever and other Aedes borne diseases in China. Methods Based on the Aedes surveillance data from the database of dengue fever research project supported by the central government, the Aedes larvae density, i. e. Breteau Index (BI), in Hainan and Yunnan provinces was analyzed to identify the areas with different risk of dengue transmission, then pass rates of BI control level in the 2 provinces were calculated. Results In February 2017, the average BI in Hainan indicated the intermediate risk of dengue fever transmission, while the average BI was higher than 5 in Jinghong, urban Mengla, Lancang port, Qinshui River port in Gengma, and Gaozhuang port in Jinghong in Yunnan, indicating the risk of outbreak caused by imported dengue fever. The average BI in Yunnan was higher than that during the same period in 2016, while the average BI in Hainan was lower than that during the same period in 2016. The pass rate of BI control level was 90% in Yunnan, but 20% in Hainan. Conclusion During January-February 2017, the average BI indicated intermediate risk of dengue fever transmission in Hainan while the low risk of dengue fever transmission in some areas in Yunnan. It is necessary to strengthen Aedes surveillance, risk assessment, prevention and control of dengue fever in key provinces in southern China to provide scientific evidence for the prevention and control of Aedes borne diseases.