Current incidence and residual risk of hepatitis B infection among blood donors in the United States.
BACKGROUND
This study used two approaches to estimate the current incidence of hepatitis B virus (HBV) in a US donor population.


METHODS
HBV incidence was estimated through the hepatitis B surface antigen (HBsAg) yield approach and the seroconversion method. Residual risk was estimated by the incidence–window period model. HBsAg yield refers to an HBsAg confirmed-positive, antibody against hepatitis B core antigen (anti-HBc)–nonreactive donation, adjusted for false-positive neutralization results. The number of HBsAg-seroconverting repeat donors divided by total number of person-years of evaluation or the HBsAg yield rate divided by HBsAg yield window gave rise to incidence estimates.


RESULTS
The seroconversion and the yield approach, respectively, gave an incidence estimate of 3.41 or 3.43 per 105 person-years. Using a revised infectious window period of 38 or 30 days for current HBsAg assays, the current residual risk for HBV was respectively estimated for 2006 to 2008 at 1 in 282,000 or 1 in 357,000 donations from the seroconversion approach and 1 in 280,000 or 1 in 355,000 donations from the yield approach. With the same database and methods, this is a decrease from 1 in 86,000 to 1 in 110,000 observed in 1997 to 1999.


CONCLUSIONS
Current HBV incidence and residual risk are lower than earlier estimates, especially in the youngest donors, but remain higher in the absence of HBV nucleic acid test than those for human immunodeficiency virus or hepatitis C virus (HCV). In addition to the exclusion of HBsAg false-positive donors, the reduction could reflect shortened window periods and decreased incidence rates due to vaccination or other reasons.
Transmissible Diseases Department, American Red Cross Blood Services, 15601 Crabbs BranchWay, Rockville MD 20855, USA. zous@usa.redcross.org
Shimian
S
Zou
Susan L
SL
Stramer
Edward P
EP
Notari
Mary C
MC
Kuhns
David
D
Krysztof
Fatemeh
F
Musavi
Chyang T
CT
Fang
Roger Y
RY
Dodd
D001782:Blood Donors; D005260:Female; D006509:Hepatitis B / Q000097:blood / Q000453:epidemiology* / Q000517:prevention & control; D006514:Hepatitis B Surface Antigens / Q000097:blood; D006801:Humans; D015994:Incidence; D008297:Male; D008954:Models, Biological; D012307:Risk Factors; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D014611:Vaccination
D006514:Hepatitis B Surface Antigens