Acute hepatitis B infection associated with blood transfusion in England and Wales, 1991-7: review of database.

Blood donations in England and Wales are collected from healthy donors who do not acknowledge factors associated with an increased risk of bloodborne infections. All donations issued for transfusion since the early 1970s have been tested for hepatitis B surface antigen as a marker of transmissible hepatitis B virus. These measures have resulted in low rates of transmission by transfusion but have not eliminated all infectious donations from the blood supply. Hepatitis B infections in transfusion recipients are investigated by the national blood services to identify if they were transmitted by transfusion. A donation is concluded as having been probably infectious if the donor was surface antigen negative but had evidence of acute infection or of carrying the virus (antibody to hepatitis B core antigen with no or low titres of antibody to surface antigen) or if the donor was surface antigen positive (on review of test results or retesting archived serum) and blood was erroneously released. Mutant strains of hepatitis B virus not detected by routine surface antigen tests also pose a risk of infectious donations being transfused. Acute hepatitis B infections, and the probable route of infection, are reported voluntarily by laboratories in England and Wales to the Communicable Disease Surveillance Centre. We examined these reports to describe the frequency and nature of acute hepatitis B infection transmitted by transfusion.