A nationwide seroprevalence of total antibody to hepatitis A virus from 2005 to 2009: age and area-adjusted prevalence rates

Abstract

Background/AimsRecent 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.MethodsRetrospective 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.ResultsThe 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%).ConclusionsThe 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.

Nationwide Seropositivity of Hepatitis A in Republic of Korea from 2005 to 2014, before and after the Outbreak Peak in 2009

“…For 25,140 subjects enrolled during 2005–2009, the mean age was 37.4 years and the male-to-female ratio was 1:0.99 as previously reported. [6] For 399,105 subjects enrolled during 2010–2014, the mean age was 37.8 years and the male-to-female ratio was 1:1.42. The male-to-female ratio was reversed in the latter half of the period, probably due to increased prenatal screening of IgG anti-HAV for women of child-bearing age after the outbreak peaked in 2009.…”

“…From January 2005 to December 2009, the results of total anti-HAV tests from 25,140 subjects (1,140 in 2005, 1,642 in 2006, 2,050 in 2007, 6,207 in 2008 and 14,101 in 2009, respectively) were analyzed based on 2005 national census data, and through previously published methods identical to that of this study [6]. Due to heightened awareness about HAV during the nationwide outbreak of hepatitis A, far more doctors and patients requested anti-HAV tests, and therefore, the sample numbers rapidly increased during this study period.…”

Antibodies against Hepatitis A and Hepatitis B Virus in Intravenous Immunoglobulin Products

“…Consequently, the seroprevalence of anti-HAV antibodies has recently been reported to be low among people under the age of 40 years in these countries (125262728293031). However, unlike the situation in Japan, the seroprevalence of anti-HAV antibodies has increased in children under the age of 10 years in Korea and the USA following the recommendation of vaccination against HAV for all children over the age of 12 months (12628).…”

High Prevalence of Symptomatic Hepatitis A Infection in Rural Area of Chaharmahal VA Bakhtiari Province, Iran

“…According to a report from Centers for Disease Control and Prevention, the most important risk factor for HAV infection is personal contact [24]. However, as a common water source was the only water supply in this region and all the affected children had the same water source, the spread of infection could have been due to water contamination.…”

“…However, as a common water source was the only water supply in this region and all the affected children had the same water source, the spread of infection could have been due to water contamination. Although, identification of risk factors of HAV infection is difficult [24], as the children are living in a rural area with very poor hygiene and low income, the high rate of symptomatic infection could be attributed to these main risk factors.…”