Infectivity of blood products from donors with occult hepatitis B virus infection.
BACKGROUND
Occult hepatitis B virus (HBV) infection (OBI) is identified in 1:1000 to 1:50,000 European blood donations. This study intended to determine the infectivity of blood products from OBI donors.


METHODS
Recipients of previous donations from OBI donors were investigated through lookback (systematic retrieval of recipients) or traceback (triggered by clinical cases). Serologic and genomic studies were undertaken on consenting donors and recipients. Multiple variables potentially affecting infectivity were examined.


RESULTS
A total of 45 of 105 (42.9%) donor-recipients pairs carried antibodies to HBV core (anti-HBc) as evidence of previous HBV infection. Subtracting 15% of anti-HBc population background, the adjusted transmission rate was 28%. Anti-HBc prevalence increased to 28 of 44 (63.8%) in unvaccinated recipients receiving anti-HBs-negative OBI blood products. In contrast, four of 26 (15.4%) recipients of anti-HBs-positive products were anti-HBc positive. Transmission with anti-HBs-negative products depended on volume of plasma transfused (85%-100% with 200 mL of fresh frozen plasma [FFP], 51% with 50 mL in platelet concentrates [PCs], and 24% with 20 mL in red blood cells [RBCs], p < 0.0001 FFP vs. RBCs). The 50% minimum infectious dose of OBI HBV DNA was estimated at 1049 (117-3441) copies. Donor and recipient strains sequence homology of at least 99% confirmed transfusion-transmitted infection in 10 cases and excluded it in one case.


CONCLUSIONS
Blood products from donors with OBI carry a high risk of HBV transmission by transfusion. This risk is dependent on presence of anti-HBs and viral dose. This may justify safety measures such as anti-HBc and HBV nucleic acid test screening depending on epidemiology.
Department of Haematology, University of Cambridge, Cambridge, UK.
Jean-Pierre
JP
Allain
Ivanka
I
Mihaljevic
Maria Isabel
MI
Gonzalez-Fraile
Knut
K
Gubbe
Lene
L
Holm-Harritshøj
Jose Maria
JM
Garcia
Ewa
E
Brojer
Christian
C
Erikstrup
Mona
M
Saniewski
Lorenz
L
Wernish
Lydia
L
Bianco
Henrik
H
Ullum
Daniel
D
Candotti
Nico
N
Lelie
Wolfram H
WH
Gerlich
Michael
M
Chudy
D000328:Adult; D000368:Aged; D001782:Blood Donors; D005260:Female; D006509:Hepatitis B / Q000635:transmission*; D006510:Hepatitis B Antibodies / Q000097:blood; D006515:Hepatitis B virus / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D012307:Risk Factors; D065227:Transfusion Reaction
D006510:Hepatitis B Antibodies