Demographic determinants of hepatitis C virus seroprevalence among blood donors.
OBJECTIVE
To measure demographic determinants of hepatitis C virus (HCV) seroprevalence among blood donors in the United States.


METHODS
Cross-sectional epidemiological study.


METHODS
Five blood centers in different regions of the United States.


METHODS
A total of 862,398 consecutive volunteer blood donors with one or more nonautologous donations from March 1992 through December 1993.


METHODS
Demographic data collection, serological screening with second-generation anti-HCV enzyme immunoassay, and confirmation with anti-HCV recombinant immunoblot.


RESULTS
There were 3126 donors with at least one blood donation confirmed HCV-seropositive, for a crude prevalence of 3.6 per 1000. Age-specific HCV seroprevalence rose from 0.5 per 1000 donors younger than 20 years to a maximum of 6.9 per 1000 in donors aged 30 to 39 years and declined in older age groups. There was interaction between age and educational attainment, with 30- to 49-year-olds with less than a high school diploma at highest risk of HCV infection (odds ratio [OR], 33.0; 95% confidence interval [CI], 23.0 to 47.2 compared with those younger than 30 years with a bachelor's degree or higher degree). Other independent risk factors for HCV seropositivity included male sex (OR, 1.9; 95% CI, 1.8 to 2.1), black race (OR, 1.7; 95% CI, 1.6 to 1.9), Hispanic ethnicity (OR, 1.3; 95% CI, 1.1 to 1.5), previous blood transfusion (OR, 2.8; 95% CI, 2.5 to 3.1), and first/only time donor status (OR, 4.2; 95% CI, 3.9 to 4.5 compared with repeat donors). Seropositivity for human T-lymphotropic virus types I and II, human immunodeficiency virus, or hepatitis B core antigen was highly associated with HCV seropositivity (OR, 10.4; 95% CI, 9.6 to 11.4 for one vs no marker).


CONCLUSIONS
Despite a low overall HCV prevalence in blood donors in the United States, there is a marked variation in HCV seroprevalence by demographic subgroup, even after controlling for prior blood transfusion, a recognized risk factor for HCV. Further study of the prevalence of other parenteral risk factors such as past injection drug use among blood donors is needed.
Murphy
E L
EL
Department of Laboratory Medicine, University of California, San Francisco 94143-0884, USA.
Bryzman
S
S
Williams
A E
AE
Co-Chien
H
H
Schreiber
G B
GB
Ownby
H E
HE
Gilcher
R O
RO
Kleinman
S H
SH
Matijas
L
L
Thomson
R A
RA
Nemo
G J
GJ
D000328:Adult; D017677:Age Distribution; D001782:Blood Donors / Q000706:statistics & numerical data*; D003430:Cross-Sectional Studies; D003710:Demography; D004522:Educational Status; D005260:Female; D016174:Hepacivirus / Q000276:immunology; D006526:Hepatitis C / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D012959:Socioeconomic Factors; D014481:United States / Q000453:epidemiology