title: Hepatitis B immunity in teenagers vaccinated as infants: an Italian 17-year follow-up study.
abstract: We assessed the persistence of hepatitis B surface antigen antibody (anti-HBs) and immune memory in a cohort of 571 teenagers vaccinated against hepatitis B as infants, 17 years earlier. Vaccinees were followed-up in 2003 and in 2010 (i.e. 10 years and 17 years after primary vaccination, respectively). When tested in 2003, 199 vaccinees (group A) had anti-HBs <10 mIU/mL and were boosted, 372 (group B) were not boosted because they had anti-HBs ≥10 mIU/mL (n = 344) or refused booster (n = 28) despite anti-HBs <10 mIU/mL. In 2010, 72.9% (416/571) of participants had anti-HBs ≥10 mIU/mL (67.3% in group A vs. 75.8% in group B; p 0.03). The geometric mean concentrations (GMCs) were similar in both groups. Between 2003 and 2010, anti-HBs concentrations in previously boosted individuals markedly declined with GMC dropping from 486 to 27.7 mIU/mL (p <0.001). Fifteen vaccinees showed a marked increase of antibody, possibly due to natural booster. In 2010, 96 individuals (37 of group A and 59 of group B) with anti-HBs <10 mIU/mL were boosted; all vaccinees of the former group and all but two of the latter had an anamnestic response. Post-booster GMC was higher in group B (895.6 vs. 492.2 mIU/mL; p 0.039). This finding shows that the immune memory for HBsAg persists beyond the time at which anti-HBs disappears, conferring long-term protection.
authors: Centro Nazionale di Epidemiologia, Sorveglianza e Promozione della Salute, Istituto Superiore di Sanitá, Rome; Dipartimento di Malattie Infettive, Parassitarie e Immunomediate, Istituto Superiore di Sanità, Rome.
authors: E
authors: E
authors: Spada
authors: L
authors: L
authors: Romanò
authors: M E
authors: ME
authors: Tosti
authors: O
authors: O
authors: Zuccaro
authors: S
authors: S
authors: Paladini
authors: M
authors: M
authors: Chironna
authors: R C
authors: RC
authors: Coppola
authors: M
authors: M
authors: Cuccia
authors: R
authors: R
authors: Mangione
authors: F
authors: F
authors: Marrone
authors: F S
authors: FS
authors: Negrone
authors: A
authors: A
authors: Parlato
authors: E
authors: E
authors: Zamparo
authors: C M
authors: CM
authors: Zotti
authors: A
authors: A
authors: Mele
authors: A R
authors: AR
authors: Zanetti
mesh_terms: D000293:Adolescent; D005260:Female; D005500:Follow-Up Studies; D006509:Hepatitis B / Q000276:immunology* / Q000517:prevention & control; D006510:Hepatitis B Antibodies / Q000276:immunology*; D006514:Hepatitis B Surface Antigens / Q000276:immunology*; D017325:Hepatitis B Vaccines / Q000008:administration & dosage* / Q000276:immunology; D006801:Humans; D007117:Immunization, Secondary; D007156:Immunologic Memory; D007223:Infant; D007558:Italy; D008297:Male
chemical_list: D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines
keywords: Booster; hepatitis B; immune memory; long-term protection; vaccination