title: Epidemiology of acute hepatitis B in a university hospital in São Paulo, Brazil: retrospective study of two five-year periods.
abstract: BACKGROUND
  HBV infection is endemic in Brazil and acute HBV infection is still a common disease.
  
  
  OBJECTIVE
  To analyze incidence, risk factors and evolution of acute HBV infection.
  
  
  METHODS
  University Hospital.
  
  
  METHODS
  357 patients with acute HBV infection, comparing two periods: 1985-1989 vs. 1990-1994.
  
  
  RESULTS
  The overall incidence declined from 50 new cases/year in 1985-89 (30% of all cases) to 25 new cases/year in 1990-94 (8% of all cases). Transmission among male homosexuals (3.9% of cases in 85-89) declined to 1.3% in 90-94 (p > 0.05). Amongst health care workers (HCW) it declined from 8.2% to 2.0% (p = 0.02). Conversely, heterosexual transmission increased from 4.8% to 10.1% (p = 0.06). Chronification of HBV infection following the acute episode was observed in 1.7%. Fulminant hepatic failure was seen in 3.4%. However, 27.2% of patients were lost to follow-up before normalization of the biochemical tests.
  
  
  CONCLUSIONS
  The different patterns of risk factors observed is probably related to measures for preventing AIDS and to HCW vaccination programs. Chronification following acute episodes was not a common event.
authors.affiliation: Discipline of Gastroenterology, Universidade Federal de São Paulo/Escola Paulista de Medicina, Brazil.
authors.forename: M L
authors.initials: ML
authors.lastname: Ferraz
authors.forename: A
authors.initials: A
authors.lastname: Yoradjian
authors.forename: A
authors.initials: A
authors.lastname: Barbieri
authors.forename: V
authors.initials: V
authors.lastname: Figueiredo
authors.forename: E
authors.initials: E
authors.lastname: Lopes Neto
authors.forename: C N
authors.initials: CN
authors.lastname: Cruz
authors.forename: A E
authors.initials: AE
authors.lastname: Silva
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D001938:Brazil / Q000453:epidemiology; D005260:Female; D006509:Hepatitis B / Q000453:epidemiology* / Q000635:transmission; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012189:Retrospective Studies