The incidence of symptomatic hepatitis A reportedly increased among 20- to 40-year-old Korean during the late 2000s. Vaccination against hepatitis A was commenced in the late 1990s and was extended to children aged <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.
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 IgG anti-HAV was compared among 12 age groups and among the following time periods: early 2000s (2001-2003), mid-to-late 2000s (2006-2008), and early 2010s (2011-2013). The chi-square test for trend was used for statistical analysis.
The seroprevalence of IgG anti-HAV did not differ significantly between the sexes. Furthermore, compared to the seroprevalence of IgG anti-HAV in the early 2000s and mid-to-late 2000s, that in the early 2010s was markedly increased among individuals aged 1-14 years and decreased among those aged 25-44 years (
The number of symptomatic HAV infection cases in Korea is decreasing, but the seroprevalence of IgG anti-HAV is low in the active population.
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A 37-year-old male presented with fever and jaundice was diagnosed as hepatitis A complicated with progressive cholestasis and severe autoimmune hemolytic anemia. He was treated with high-dose prednisolone (1.5 mg/kg), and eventually recovered. His initial serum contained genotype IA hepatitis A virus (HAV), which was subsequently replaced by genotype IIIA HAV. Moreover, at the time of development of hemolytic anemia, he became positive for immunoglobulin M (IgM) anti-hepatitis E virus (HEV). We detected HAV antigens in the liver biopsy specimen, while we detected neither HEV antigen in the liver nor HEV RNA in his serum. This is the first report of hepatitis A coinfected with two different genotypes manifesting with autoimmune hemolytic anemia, prolonged cholestasis, and false-positive IgM anti-HEV.
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Recent outbreak of hepatitis A in Korea is clearly related to the epidemiological shift of hepatitis A virus (HAV). However, nationwide seroprevalence data have been limited. This study estimated the nationwide, age- and area-adjusted anti-HAV prevalence from 2005 to 2009.
Retrospective analysis of the results of total anti-HAV test in 25,140 cases which were requested by 1,699 medical institutions throughout the nation to Seoul Clinical Laboratory from Jan. 1 2005 to Dec. 31 2009 was performed. The estimated seroprevalence was adjusted by area and age of the standard population based on the 2005 Census data from Korea National Statistical Office.
The area-adjusted anti-HAV prevalence in the children younger than 10 years were 33.4% in 2005 and 69.9% in 2009. The most susceptible age groups to HAV infection during the last 5 years were teenagers and the young adults in their age of twenties. The area-adjusted seroprevalence in 2009 were 11.9% in the age group of 20-29 years, 23.4% in the age group of 10-19 years, 48.4% in the age group of 30-39 years. The population in 40-49 years showed geographically different seroprevalence with the lowest rate in Seoul (80%).
The most susceptible age group to HAV infection is 10-29 years, while the young children less than 10 years showed about 70% seropositivity. The changing seroepidemiology should be monitored continuously for the proper vaccination and patient care.
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