Analysis of the Epidemic Dynamics of Hepatitis A from 1990 to 2003 in Qing Dao City

Objective This study was designed to get a further insight into the epidemic situation of hepatitis A in Qingdao city to benefit to the prediction of its epidemic trends and the formulation of effective preventive and therapeutic measures and emergency plans．Methods The incidence and epidemic characteristics of hepatitis A from 1990 to 2003 were analyzed．Meanwhile，1370 healthy residents were randomly selected in 2000 and 2002，with their antibody levels of hepatitis A determined．Results The incidence of the disease in Qingdao city ranged from 1.44 to 124.42/100.000 with an average of 57.58 of 100.000．There was an epidemic peak in 1991．And then a decrease trend of the incidence was seen year after year．There have been only sporadic cases in recent years，with individual cases observed all around the year. In spring，the incidence peaked and it was much higher in the city than in the countryside．Children were mostly involved with males affected more than females．The rate of positive antibody in younger age group was rather lower．Conclusion There is a potential risk of hepatitis A spreading in Qing Dao City．And the prevention and treatment for younger age group should be taken seriously and particular attention should be paid to the cities and regions where there are more floating population．