Low level of immunity against hepatitis A among Korean adolescents: Vaccination rate and related factors

American Journal of Infection Control
Vol 41 | No. 10 | October 2013 | Pages 853-948
http://www.ajicjournal.org/current

Low level of immunity against hepatitis A among Korean adolescents: Vaccination rate and related factors
Jung Yeon Heo, MD, Joon Young Song, MD, Ji Yun Noh, MD, Yu Bin Seo, MD, In Sun Kim, MD,     Won Suk Choi, MD, Woo Joo Kim, MD, PhD, Gum Joo Cho, MD, Taik Gun Hwang, MD, Hee Jin Cheong, MD, PhD
http://www.ajicjournal.org/article/S0196-6553%2813%2900667-6/abstract

Abstract
Background
We evaluated the current vaccination rate and immunity in the Korean adolescent population and analyzed their parents’ attitudes toward hepatitis A virus (HAV) vaccination.

Methods
Between March and April 2011, sera were collected for immunoglobulin (Ig) G anti-HAV testing from students in their first year of high school from 12 different high schools located in southwestern Seoul. Simultaneously, questionnaires were given to the parents of the students to evaluate factors related to HAV vaccination, including demographics, HAV vaccination status, reason for getting the vaccination, and awareness regarding HAV.

Results
Sera from 2,879 subjects and questionnaires from their parents were collected. The HAV vaccination rate among adolescents aged between 14 and 17 years was 18.9%, and the seroprevalence was 15.4%. Among subjects who reported receiving the HAV vaccination, the IgG anti-HAV seropositivity rate was only 42.2%. For subjects who were not vaccinated, the IgG anti-HAV seropositivity rate was 9.1%. The most significant reason for receiving the vaccination was recommendation from health care providers; the most important source of information regarding the vaccination was public health organizations.

Conclusion
HAV vaccination rate and anti-HAV seroprevalence in Korean adolescents was low; the seropositivity rate in the vaccinated group was lower than expected. Actively recommending HAV vaccination in this group is required, and routine, nationwide, government-sponsored vaccination of adolescents against HAV should be considered.