title: The prevalence of hepatitis C virus infection in the United States, 1988 through 1994.
abstract: BACKGROUND
  Because many persons with chronic hepatitis C virus (HCV) infection are asymptomatic, population-based serologic studies are needed to estimate the prevalence of the infection and to develop and evaluate prevention efforts.
  
  
  METHODS
  We performed tests for antibody to HCV (anti-HCV) on serum samples from 21,241 persons six years old or older who participated in the third National Health and Nutrition Examination Survey, conducted during 1988 through 1994. We determined the prevalence of HCV RNA by means of nucleic acid amplification and the genotype by means of sequencing.
  
  
  RESULTS
  The overall prevalence of anti-HCV was 1.8 percent, corresponding to an estimated 3.9 million persons nationwide (95 percent confidence interval, 3.1 million to 4.8 million) with HCV infection. Sixty-five percent of the persons with HCV infection were 30 to 49 years old. Seventy-four percent were positive for HCV RNA, indicating that an estimated 2.7 million persons in the United States (95 percent confidence interval, 2.4 million to 3.0 million) were chronically infected, of whom 73.7 percent were infected with genotype 1 (56.7 percent with genotype 1a, and 17.0 percent with genotype 1b). Among subjects 17 to 59 years of age, the strongest factors independently associated with HCV infection were illegal drug use and high-risk sexual behavior. Other factors independently associated with infection included poverty, having had 12 or fewer years of education, and having been divorced or separated. Neither sex nor racial-ethnic group was independently associated with HCV infection.
  
  
  CONCLUSIONS
  In the United States, about 2.7 million persons are chronically infected with HCV. People who use illegal drugs or engage in high-risk sexual behavior account for most persons with HCV infection.
authors.affiliation: Hepatitis Branch, Division of Viral and Rickettsial Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.
authors.forename: M J
authors.initials: MJ
authors.lastname: Alter
authors.forename: D
authors.initials: D
authors.lastname: Kruszon-Moran
authors.forename: O V
authors.initials: OV
authors.lastname: Nainan
authors.forename: G M
authors.initials: GM
authors.lastname: McQuillan
authors.forename: F
authors.initials: F
authors.lastname: Gao
authors.forename: L A
authors.initials: LA
authors.lastname: Moyer
authors.forename: R A
authors.initials: RA
authors.lastname: Kaslow
authors.forename: H S
authors.initials: HS
authors.lastname: Margolis
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D005260:Female; D005838:Genotype; D016174:Hepacivirus / Q000145:classification / Q000235:genetics; D018937:Hepatitis C Antibodies / Q000097:blood; D019698:Hepatitis C, Chronic / Q000453:epidemiology* / Q000821:virology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009749:Nutrition Surveys; D015995:Prevalence; D012367:RNA, Viral / Q000097:blood; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D012959:Socioeconomic Factors; D014481:United States / Q000453:epidemiology; D014766:Viremia / Q000453:epidemiology
chemical_list: D018937:Hepatitis C Antibodies; D012367:RNA, Viral