Epidemiological analysis of viral hepatitis B in Ningbo,1990 - 2008

Objective To analyze the epidemiological characteristics of viral hepatitis B in Ningbo from 1990 to 2008. Methods Descriptive epidemiological analysis of the data on hepatitis B in Ningbo from 1990 to 2008 was conducted. Results From 1990 to 2008, a total of 42 469 cases of hepatitis B were reported in Ningbo with an annually average incidence of 39.05/lakh. With the incidence ranging from 24.46/lakh to 53.99/lakh, patients at the age of 20-44 accounted for 67.38% of the overall. In the duration from 2002 to 2008, the constituent ratio of affected children aged 0-7 years fell to 0.96%, from 6.40% in 1990 and 1991, with a sex ratio of 2.73 to 1. As with occupational distribution, farmers and laborers were the ailing majority constituting 46.64% and 18.56% of the whole, respectively. Conclusion The overall incidence of hepatitis B was declining in Ningbo from 1990 to 2008, which was higher in rural areas than the urban. Without noticeable seasonal incidence peak, scattered patients were commonly observed, and most cases were young adults, males outnumbering females. Furthermore, sharp decrease was shown in the constituent ratio of affected children at the age of 0-7 years.