Seroprevalence of Hepatitis-B infection amongst Taiwanese university students 18 years following the commencement of a national Hepatitis-B vaccination program

✍ Scribed by Fu-Hsiung Su; Jong-Dar Chen; Shu-Hsing Cheng; Ching-Hung Lin; Yi-Hui Liu; Fang-Yeh Chu

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 110 KB
• Volume: 79
• Category: Article
• ISSN: 0146-6615
• DOI: 10.1002/jmv.20771

✦ Synopsis

Abstract

In Taiwan, the nation‐wide Hepatitis‐B virus (HB) vaccination program was first launched in July 1984 and was directed to those infants born to hepatitis B surface antigen (HBsAg) carrier mothers in Taiwan. From July 1986 onwards, all infants born in Taiwan were immunized against HB. This study examined the HB‐infection status amongst students at a Taiwanese university 18 years subsequent to the implementation of universal HB vaccination. A total of 1,969 new university entrants in 2005 were grouped into 1 of 3 distinct birth cohorts according to their HB‐vaccination schedule (cohort‐1 students born prior to July 1, 1984; cohort‐3 students born subsequent to June 30, 1986) and were examined for their serum HBsAg, antibody to hepatitis B surface antigen (anti‐HBs), and antibody to hepatitis B core antigen (anti‐HBc) status. Immunity arising from vaccination was defined as an anti‐HBs level 10 mIU/ml. We observed a trend toward a decreasing anti‐HBc‐positive rate and a decreasing HBsAg carrier rate from, respectively, 26.5 and 8.7% for cohort‐1 to 4.7 and 1.7% for cohort‐3 students. The prevalence of students featuring seronegativity for all three HB markers increased from 12.3% for cohort‐1 to 48.8% for cohort‐3 individuals. Amongst the 1,695 subjects revealing seronegativity for HBsAg and anti‐HBc, their anti‐HBs level was analyzed according to their birth year. The prevalence of students featuring a non‐protective anti‐HBs level increased from 11.9% for birth‐year 1984 individuals to 48.2% for birth‐year 1987 students. The introduction of HB vaccine has effectively reduced the transmission of HBV infection in Taiwan, 18 years subsequent to the commencement of the universal HB‐vaccination program. A “waning‐off” effect of anti‐HBs seropositivity acquired from the HB vaccination program has also been observed. J. Med. Virol. 79:138–143, 2007. © 2006 Wiley‐Liss, Inc.