Continuing Decrease in Hepatitis B Virus Infection 30 Years After Initiation of Infant Vaccination Program in Taiwan

• Published in: Clinical gastroenterology and hepatology Vol. 14; no. 9; pp. 1324 - 1330
• Main Authors: Ni, Yen-Hsuan, Chang, Mei-Hwei, Jan, Chyi-Feng, Hsu, Hong-Yuan, Chen, Huey-Ling, Wu, Jia-Feng, Chen, Ding-Shinn
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.09.2016
• Subjects: Adolescent; Adult; Age Distribution; Child; Child, Preschool; DNA, Viral - genetics; Female; Gastroenterology and Hepatology; Genotype; Genotyping Techniques; Hepatitis B - epidemiology; Hepatitis B - prevention & control; Hepatitis B Antibodies - blood; Hepatitis B Surface Antigens - blood; Hepatitis B Vaccines - administration & dosage; Hepatitis B virus - isolation & purification; Humans; Immunization; Immunization Programs; Infant; Liver Disease; Male; Middle Aged; Prevention; Seroepidemiologic Studies; Seroepidemiology; Taiwan - epidemiology; Viral Load; Young Adult; Seroepidemiology; Prevention; anti-HBc; anti-HBs; Immunization; HBeAg; HBsAg; Liver Disease; HBV; anti-HBe; hepatitis B core antibody; hepatitis B surface antigen; hepatitis B virus; hepatitis B surface antibody; hepatitis B e antigen; hepatitis B e antigen antibody
• ISSN: 1542-3565; 1542-7714
• DOI: 10.1016/j.cgh.2016.04.030

Taiwan began a universal hepatitis B virus (HBV) vaccination program for infants in July 1984. The seroprevalence of hepatitis B surface antigen (HBsAg) decreased from 9.8% before the vaccination program to less than 1% by 25 years afterward. We continued to monitor HBV infections in this population. We conducted a series of serologic and epidemiologic surveys in the Taipei metropolitan area every 5 years from 1984 through 2014. From January 1 through December 31 of 2014, we collected serum samples from 4605 apparently healthy individuals (ages: 287 were <3 y, 405 were 3–6 y, 675 were 7–12 y, 686 were 13–18 y, 468 were 18–22 y, and 2084 were 22–50 y). All subjects were tested for HBsAg, its antibody (anti-HBs), and hepatitis B core antibody (anti-HBc). We performed genotype and viral load analyses for patients who tested positive for anti-HBc. Of vaccinated participants (age, <30 y; n = 3299), 0.5% tested positive for HBsAg, 47.4% tested positive for anti-HBs, and 4.5% tested positive for anti-HBc. Of unvaccinated participants (age, 30–50 y, n = 1306), 6.7% tested positive for HBsAg (P < .0001), 69.4% tested positive for anti-HBs, and 44.1% tested positive for anti-HBc. One occult HBV infection was found in each age group. Among subjects positive for HBsAg younger than age 30, 77% were born to mothers positive for HBsAg. Based on a series of serologic and epidemiologic surveys performed in the Taipei metropolitan area, 6.7% of persons born before the universal HBV vaccination program were positive for HBsAg, compared with 0.5% of those born afterward. Most subjects positive for HBsAg younger than age 30 were born to mothers positive for HBsAg.