Analysis of epidemiological characteristics of hepatitis A in Ningbo,1999 - 2008

Objective The study was conducted to analyze the epidemic trends and epidemiological characteristics of hepatitis A in Ningbo. Methods Descriptive epidemiological analysis of the hepatitis A surveillance data in Ningbo from 1999 to 2008 was conducted. Results With an annually averaged value of 9.9/lakh, the incidence of hepatitis A in Ningbo ranged from 4.12/lakh to 20.53/lakh, 1999 - 2008, which peaked in 1999 and declined gradually afterwards. The patients were reported from all 11 counties of Ningbo, and particularly higher incidence rates were noticed in specific counties or districts, with significant differences in the incidence between these areas (P0.001). People aged 20-39 years were mostly affected, accounting for 48.87% of all cases, while male patients outnumbered female ones with significantly different incidence rates (P0.001). As the primarily suffering occupation, farmers accounted for 40.58% of all cases. Conclusion Despite low and annually decreasing incidence of hepatitis A as the result of effective prevention and control strategies in Ningbo, food and water management and the control measures for susceptible populations, particularly young adults and farmers, should be strengthened.