Persistence of anti-HBs 5 years after the introduction of routine infant and adolescent vaccination in Italy

• Published in: Vaccine 2001-04, Vol.19 (20), p.2812-2818
• Main Authors: Faustini, A, Franco, E, Sangalli, M, Spadea, T, Calabrese, R.M, Cauletti, M, Perucci, C.A
• Format: Article
• Language: English
• Subjects: Adolescent; Age Factors; Biological and medical sciences; Child; Child, Preschool; Epidemiology. Vaccinations; General aspects; Hepatitis B Antibodies - blood; Hepatitis B vaccine; Hepatitis B Vaccines - immunology; Hepatitis B virus; Humans; Immunization, Secondary; Infant; Infant, Newborn; Infectious diseases; Italy; Long-term anti-HBs levels; Medical sciences; Multivariate Analysis; Population survey; Time Factors; Vaccination
• ISSN: 0264-410X; 1873-2518
• DOI: 10.1016/S0264-410X(01)00005-6

A population survey was conducted to assess the duration of anti-HBs levels>10 IU/l in vaccinees living in Lazio Region (Italy) 5 years after the introduction (15 June 1991) of compulsory vaccination of new-borns and 11-year-old children. A random sample of 1192 (533 children born in 1991–92 and 659 adolescents born in 1979–81) was selected. In 92.9% of children and 94.1% of adolescents anti-HBs titres were protective (≥10 IU/l). These subjects with protective titres were divided into three categories: low responders (anti-HBs titres=10–500 IU/l), medium responders (anti-HBs titres=501–2000 IU/l) and high responders (anti-HBs titres>2000 IU/l). Factors associated with the level of response were analysed, using a multiple politomic logistic regression analysis. Greater age at first dose (11–12 years) was associated with higher titres (OR=2.1, 95% CI=1.4–3.2 for medium responders and OR=3.0, 95% CI=1.9–4.8 for high responders). Simultaneous administration of DT vaccine was associated with lower titres (OR=0.4, 95% CI=0.2–0.8 for medium responders and OR=0.3, 95% CI=0.1–0.7 for high responders).