The age-specific seroprevalence of hepatitis A virus antibody in Korea

BACKGROUNDS AND AIMS: The epidemiology of hepatitis A is associated with socioeconomic and hygiene status. Recently, the prevalence of hepatitis A in young adults has been steadily increasing in Korea. This study is to investigate the age-specific seroprevalence of hepatitis A virus in Korea. METHODS: Stored sera from 250 healthy adult subjects who visited the health promotion center in Samsung Medical Center between July and August 2006 were tested for IgG hepatitis A virus antibody (anti-HAV). RESULTS: The prevalence of anti-HAV was 2%, 72%, 92%, 94%, 100% in 20's, 30's, 40's, 50's, and 60's, respectively. The prevalence of anti-HAV was significantly lower in subjects below age 40 compared to those above 40 (37.0% vs. 95.3%, p<0.001). The seroprevalence was higher in area outside of Seoul compared to those living in Seoul in age group below 40 (25.6% vs. 55.6%, p=0.01). In Seoul area, the prevalence was significantly lower in Kangnam-Gu, Seocho-Gu, and Songpa-Gu district compared to the other areas of Seoul in the age group below 40 (20.0% vs. 42.1%, p<0.05). CONCLUSION: The seroprevalence of hepatitis A virus antibody in Korean population below 40 is quite low and immunity to hepatitis A virus in those subjects can be a public health issue. In view of changing seroepidemiology, a policy for hepatitis A vaccination in population below 40 might be warranted.