title: Effectiveness of hepatitis A vaccination as post-exposure prophylaxis.
abstract: Hepatitis A (HA) has been a vaccine-preventable disease since 1995. In Catalonia, a universal combined hepatitis A+B vaccination program of preadolescents was initiated at the end of 1998. However, outbreaks are reported each year and post-exposure prophylaxis (PEP) with hepatitis A virus (HAV) vaccine or immunoglobulin (IG) is recommended to avoid cases. The aim of this study was to assess the effectiveness of HAV vaccine and IG in preventing hepatitis A cases in susceptible exposed people. A retrospective cohort study of contacts of HA cases involved in outbreaks reported in Catalonia between January 2006 and December 2012 was made. The rate ratios and 95% confidence intervals (CI) of HA in susceptible contacts receiving HAV or IG versus those without PEP were calculated. There were 3550 exposed persons in the outbreaks studied: 2381 received one dose of HAV vaccine (Hepatitis A or hepatitis A+B), 190 received IG, and 611 received no PEP. 368 exposed subjects received one dose of HAV vaccine and IG simultaneously and were excluded from the study. The effectiveness of PEP was 97.6% (95% CI 96.2-98.6) for HAV vaccine and 98.3% (95% CI 91.3-99.9) for IG; the differences were not statistically significant (p = 0.36). The elevated effectiveness of HAV vaccination for PEP in HA outbreaks, similar to that of IG, and the long-term protection of active immunization, supports the preferential use of vaccination to avoid secondary cases.
authors.affiliation: a Agència de Salut Pública de Catalunya, Generalitat de Catalunya , Barcelona , Spain.
authors.forename: Ignasi
authors.initials: I
authors.lastname: Parrón
authors.affiliation: a Agència de Salut Pública de Catalunya, Generalitat de Catalunya , Barcelona , Spain.
authors.forename: Caritat
authors.initials: C
authors.lastname: Planas
authors.affiliation: a Agència de Salut Pública de Catalunya, Generalitat de Catalunya , Barcelona , Spain.|b CIBER Epidemiología y Salud pública (CIBERESP) , Madrid , Spain.
authors.forename: Pere
authors.initials: P
authors.lastname: Godoy
authors.affiliation: b CIBER Epidemiología y Salud pública (CIBERESP) , Madrid , Spain.|c Agència de Salut Pública de Barcelona , Barcelona , Spain.
authors.forename: Sandra
authors.initials: S
authors.lastname: Manzanares-Laya
authors.affiliation: a Agència de Salut Pública de Catalunya, Generalitat de Catalunya , Barcelona , Spain.|b CIBER Epidemiología y Salud pública (CIBERESP) , Madrid , Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Martínez
authors.affiliation: a Agència de Salut Pública de Catalunya, Generalitat de Catalunya , Barcelona , Spain.
authors.forename: Maria Rosa
authors.initials: MR
authors.lastname: Sala
authors.affiliation: a Agència de Salut Pública de Catalunya, Generalitat de Catalunya , Barcelona , Spain.
authors.forename: Sofia
authors.initials: S
authors.lastname: Minguell
authors.affiliation: a Agència de Salut Pública de Catalunya, Generalitat de Catalunya , Barcelona , Spain.|b CIBER Epidemiología y Salud pública (CIBERESP) , Madrid , Spain.|d Departament de Medicina . Universitat de Barcelona , Barcelona , Spain.
authors.forename: Nuria
authors.initials: N
authors.lastname: Torner
authors.affiliation: a Agència de Salut Pública de Catalunya, Generalitat de Catalunya , Barcelona , Spain.|b CIBER Epidemiología y Salud pública (CIBERESP) , Madrid , Spain.
authors.forename: Mireia
authors.initials: M
authors.lastname: Jané
authors.affiliation: b CIBER Epidemiología y Salud pública (CIBERESP) , Madrid , Spain.|d Departament de Medicina . Universitat de Barcelona , Barcelona , Spain.
authors.forename: Angela
authors.initials: A
authors.lastname: Domínguez
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003362:Cost-Benefit Analysis; D005260:Female; D006506:Hepatitis A / Q000191:economics / Q000517:prevention & control*; D022362:Hepatitis A Vaccines / Q000008:administration & dosage / Q000191:economics*; D006801:Humans; D007116:Immunization, Passive / Q000191:economics* / Q000379:methods; D016756:Immunoglobulins, Intravenous / Q000008:administration & dosage / Q000191:economics*; D008297:Male; D056990:Post-Exposure Prophylaxis / Q000191:economics* / Q000379:methods; D012189:Retrospective Studies; D013030:Spain; D014611:Vaccination / Q000191:economics* / Q000379:methods; D055815:Young Adult
chemical_list: D022362:Hepatitis A Vaccines; D016756:Immunoglobulins, Intravenous
keywords: Hepatitis A; effectiveness; immune globulin; outbreak; post-exposure prophylaxis; vaccine