title: Prevalence and risk factors of Hepatitis C virus infection in Brazil, 2005 through 2009: a cross-sectional study.
abstract: BACKGROUND
  Hepatitis C chronic liver disease is a major cause of liver transplant in developed countries. This article reports the first nationwide population-based survey conducted to estimate the seroprevalence of HCV antibodies and associated risk factors in the urban population of Brazil.
  
  
  METHODS
  The cross sectional study was conducted in all Brazilian macro-regions from 2005 to 2009, as a stratified multistage cluster sample of 19,503 inhabitants aged between 10 and 69 years, representing individuals living in all 26 State capitals and the Federal District. Hepatitis C antibodies were detected by a third-generation enzyme immunoassay. Seropositive individuals were retested by Polymerase Chain Reaction and genotyped. Adjusted prevalence was estimated by macro-regions. Potential risk factors associated with HCV infection were assessed by calculating the crude and adjusted odds ratios, 95% confidence intervals (95% CI) and p values. Population attributable risk was estimated for multiple factors using a case-control approach.
  
  
  RESULTS
  The overall weighted prevalence of hepatitis C antibodies was 1.38% (95% CI: 1.12%-1.64%). Prevalence of infection increased in older groups but was similar for both sexes. The multivariate model showed the following to be predictors of HCV infection: age, injected drug use (OR = 6.65), sniffed drug use (OR = 2.59), hospitalization (OR = 1.90), groups socially deprived by the lack of sewage disposal (OR = 2.53), and injection with glass syringe (OR = 1.52, with a borderline p value). The genotypes 1 (subtypes 1a, 1b), 2b and 3a were identified. The estimated population attributable risk for the ensemble of risk factors was 40%. Approximately 1.3 million individuals would be expected to be anti-HCV-positive in the country.
  
  
  CONCLUSIONS
  The large estimated absolute numbers of infected individuals reveals the burden of the disease in the near future, giving rise to costs for the health care system and society at large. The known risk factors explain less than 50% of the infected cases, limiting the prevention strategies. Our findings regarding risk behaviors associated with HCV infection showed that there is still room for improving strategies for reducing transmission among drug users and nosocomial infection, as well as a need for specific prevention and control strategies targeting individuals living in poverty.
authors: Universidade de Pernambuco, Faculdade de Ciências Médicas de Pernambuco, Hospital Universitário Oswaldo Cruz, Rua Arnóbio Marques, 310, Santo Amaro, CEP: 50100-130, Recife, PE, Brazil.
authors: Leila M M B
authors: LM
authors: Pereira
authors: Celina M T
authors: CM
authors: Martelli
authors: Regina C
authors: RC
authors: Moreira
authors: Edgar
authors: E
authors: Merchan-Hamman
authors: Airton T
authors: AT
authors: Stein
authors: Maria Regina A
authors: MR
authors: Cardoso
authors: Gerusa M
authors: GM
authors: Figueiredo
authors: Ulisses R
authors: UR
authors: Montarroyos
authors: Cynthia
authors: C
authors: Braga
authors: Marília D
authors: MD
authors: Turchi
authors: Gabriela
authors: G
authors: Coral
authors: Deborah
authors: D
authors: Crespo
authors: Maria Luiza C
authors: ML
authors: Lima
authors: Luis Claudio A
authors: LC
authors: Alencar
authors: Marcelo
authors: M
authors: Costa
authors: Alex A
authors: AA
authors: dos Santos
authors: Ricardo A A
authors: RA
authors: Ximenes
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001938:Brazil / Q000453:epidemiology; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D005838:Genotype; D016174:Hepacivirus / Q000235:genetics / Q000276:immunology; D006526:Hepatitis C / Q000453:epidemiology* / Q000266:history; D018937:Hepatitis C Antibodies / Q000097:blood / Q000276:immunology; D049674:History, 21st Century; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D015995:Prevalence; D012307:Risk Factors; D014505:Urban Population; D055815:Young Adult
chemical_list: D018937:Hepatitis C Antibodies
references: Trans R Soc Trop Med Hyg. 2006 Jul;100(7):663-8
references: 16386279
references: Am J Epidemiol. 1985 Nov;122(5):904-14
references: 4050778
references: Clin Infect Dis. 2008 Jun 15;46(12):1852-8
references: 18462109
references: Rev Saude Publica. 2009 Aug;43 Suppl 1:43-50
references: 19669064
references: J Viral Hepat. 2010 Jun;17(6):435-43
references: 19780936
references: Am J Trop Med Hyg. 2009 Aug;81(2):240-7
references: 19635877
references: Nature. 2009 Oct 8;461(7265):798-801
references: 19759533
references: Cad Saude Publica. 2008;24 Suppl 4:s545-57
references: 18797730
references: Cad Saude Publica. 2010 Sep;26(9):1693-704
references: 20877930
references: AIDS Res Hum Retroviruses. 2012 Feb;28(2):215-9
references: 21790472
references: Lancet Infect Dis. 2005 Sep;5(9):558-67
references: 16122679
references: Rev Saude Publica. 2003 Dec;37(6):751-9
references: 14666305
references: N Engl J Med. 1999 Aug 19;341(8):556-62
references: 10451460
references: Euro Surveill. 2008 May 22;13(21):
references: 18761967
references: J Med Virol. 2008 Jan;80(1):53-7
references: 18041005
references: Int J Epidemiol. 2008 Aug;37(4):852-61
references: 18653514
references: MMWR Surveill Summ. 2009 May 22;58(3):1-27
references: 19478727
references: J Med Virol. 2010 Apr;82(4):546-55
references: 20166185
references: Braz J Infect Dis. 1998 Dec;2(6):269-284
references: 11103019
references: Rev Soc Bras Med Trop. 2008 May-Jun;41(3):238-42
references: 18719801
references: Am J Public Health. 2000 Oct;90(10):1562-9
references: 11029989
references: Clin Liver Dis. 2010 Feb;14(1):1-21, vii
references: 20123436
references: Mem Inst Oswaldo Cruz. 2001 Aug;96(6):765-9
references: 11562698
references: Euro Surveill. 2008 May 22;13(21):
references: 18761963
references: Mem Inst Oswaldo Cruz. 2008 Jun;103(4):405-8
references: 18660998
references: Braz J Infect Dis. 2010 Sep-Oct;14(5):483-8
references: 21221477
references: J Clin Virol. 2009 Mar;44(3):200-6
references: 19195927
references: Braz J Infect Dis. 2002 Aug;6(4):172-80
references: 12204184
references: J Viral Hepat. 2006 Jan;13(1):34-41
references: 16364080
references: Lancet. 2011 Jun 11;377(9782):2042-53
references: 21561659
references: Liver Int. 2011 Jul;31 Suppl 2:18-29
references: 21651701
references: Ann Intern Med. 2006 May 16;144(10):705-14
references: 16702586
references: Eur J Public Health. 2009 Oct;19(5):527-33
references: 19667051
references: NCHS Data Brief. 2010 Mar;(27):1-8
references: 20223109
references: Braz J Med Biol Res. 2005 Jan;38(1):41-9
references: 15665987
references: World J Gastroenterol. 2007 May 7;13(17):2436-41
references: 17552026
references: Cien Saude Colet. 2010 May;15(3):663-70
references: 20464178