Epidemiology of Japanese encephalitis in Ningbo city in Zhejiang province,2005-2010

Objective To analyze the epidemiological characteristics of Japanese encephalitis (JE) in Ningbo from 2005 to 2010 and provide scientific evidence for the disease prevention and control in the future. Methods The analysis was conducted on the surveillance data of JE in Ningbo during this period. Results A total of 136 JE cases were reported, including 16 deaths. The average annual incidence and case fatality were the scattered 0.40/lakh and 11.76% respectively, the incidence was highest in 2006 (0.80/lakh) and lowest in 2010 (0.12/lakh). The seasonality of the disease was obvious, and the cases mainly occurred during June-September with the incidence peak in July. The majority of cases were the scattered children in rural population and in floating population. (52.94%), the youngest was only 2 months old. Totally 8.82% of the cases occurred in people aged15 years, the oldest was 77 years old. Conclusion It is necessary to strengthen JE vaccination, improve environment sanitation and conduct health education in rural area and in zone joining urban and rural areas with dense floating population to improve herd immunity and prevent/control JE effectively.