Changes in the seroprevalence of IgG anti-hepatitis A virus between 2001 and 2013: experience at a single center in Korea

Background/Aims: The incidence of symptomatic hepatitis A reportedly increased among 20- to 40-year-old Koreanduring the late 2000s. Vaccination against hepatitis A was commenced in the late 1990s and was extended to childrenaged <10 years. In the present study we analyzed the changes in the seroprevalence of IgG anti-hepatitis A virus (HAV)over the past 13 years.Methods: Overall, 4903 subjects who visited our hospital between January 2001 and December 2013 were studied.The seroprevalence of IgG anti-HAV was analyzed according to age and sex. In addition, the seroprevalence of IgGanti-HAV was compared among 12 age groups and among the following time periods: early 2000s (2001-2003), midto-late 2000s (2006-2008), and early 2010s (2011-2013). The chi-square test for trend was used for statistical analysis.Results: The seroprevalence of IgG anti-HAV did not differ significantly between the sexes. Furthermore, comparedto the seroprevalence of IgG anti-HAV in the early 2000s and mid-to-late 2000s, that in the early 2010s was markedlyincreased among individuals aged 1-14 years and decreased among those aged 25-44 years (P<0.01). We also foundthat the seroprevalence of IgG anti-HAV in individuals aged 25-44 years in the early 2010s was lower than that in theearly 2000s and mid-to-late 2000s.Conclusions: The number of symptomatic HAV infection cases in Korea is decreasing, but the seroprevalence of IgGanti-HAV is low in the active population. (Clin Mol Hepatol 2014;20:162-167