Surveillance for malaria in Dinghai of Zhoushan, Zhejiang, 1988-2012

Objective To understand the incidence of malaria in Dinghai district of Zhoushan islands, Zhejiang province from 1988 to 2012 and provide evidence for the prevention and control of malaria. Methods The incidence data of malaria in Dinghai during this period were collected for statistical analysis. Results A total of 46 malaria cases were detected with an average annual incidence of 0.05/lakh. The incidence showed a slight rise during 2006-2008. Totally 25 429 local residents received blood examination with positive rate of 0.04%, and 1763 persons from places received blood examination with the positive rate of 3.51%. The imported cases accounted for 82.61% of the total malaria cases in Dinghai (38/46), and the imported cases in floating population accounted for 71.05% of the total imported cases (27/38). Conclusion After malaria was eliminated basically in Zhoushan, imported malaria cases still occurred. It is essential to strengthen the surveillance of malaria in floating population to prevent imported malaria.