title: Hepatitis A among men who have sex with men in Barcelona, 1989-2010: insufficient control and need for new approaches.
abstract: BACKGROUND
  Men who have sex with men (MSM) are a known group at risk for hepatitis A and outbreaks among this group are frequent. In Barcelona, vaccination for MSM has been recommended since 1994. In 1998 a vaccination campaign among preadolescents was implemented and an immunization program in gay bathhouses began in 2004.
  
  
  OBJECTIVE
  to asses the incidence of hepatitis A in adults in Barcelona from 1989 to 2010 and to evaluate the outbreaks among MSM including all genotypes involved.
  
  
  METHODS
  All cases of acute hepatitis A among young adults notified to the Public Health Agency of Barcelona from 1989 to 2010 were included for analyses. We calculated the annual incidence rate and the incidence ratio male-to-female (M:F) as a marker for MSM. Spearman's coefficient was used to evaluate trends. We also evaluated the outbreaks among MSM and compared their characteristics using Chi-squared and ANOVA test. Fragment amplification of the VP1/P2A region was used for genetic analysis.
  
  
  RESULTS
  The median annual incidence for the period of study was 4.7/100000 among females and 11.7/100000 among males. The rate of hepatitis A for adult woman decreased over time (Spearman' coefficient = -0.63, p = 0.002), whereas there was no decrease for adult men (Spearman' coefficient = 0.097, p = 0.67). During the study period the M:F ratio increased (Spearman' coefficient = 0.73, p < 0.001).Three large outbreaks among MSM were detected. When comparing outbreaks, there was a decrease in the percentage of bathhouse users (from 47% to 19%, p = 0.0001) and sex workers (from 6.5% to 0%) while the percentage of HIV infected individuals did not change significantly (range: 21%-28%, p = 0.36). The isolated strains were closely related to those circulating in Europe.
  
  
  CONCLUSIONS
  Annual incidences remain high among MSM without tendency to decrease. More strategies which effectively reach the whole MSM community are needed.
authors.affiliation: Epidemiology Department, Public Health Agency of Barcelona (ASPB), Pl, Lesseps,1, 08023 Barcelona, Spain. ctortaja@aspb.cat
authors.forename: Cecilia
authors.initials: C
authors.lastname: Tortajada
authors.forename: Patricia G
authors.initials: PG
authors.lastname: de Olalla
authors.forename: Elia
authors.initials: E
authors.lastname: Diez
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Pinto
authors.forename: Albert
authors.initials: A
authors.lastname: Bosch
authors.forename: Unai
authors.initials: U
authors.lastname: Perez
authors.forename: Milagros
authors.initials: M
authors.lastname: Sanz
authors.forename: Joan A
authors.initials: JA
authors.lastname: Caylà
mesh_terms: D000328:Adult; D004196:Disease Outbreaks; D005260:Female; D006506:Hepatitis A / Q000453:epidemiology* / Q000517:prevention & control*; D018451:Homosexuality, Male; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D013030:Spain / Q000453:epidemiology