HEPATITIS-B CORE ANTIBODY SCREENING OF VOLUNTARY BLOOD-DONORS - AN EXTENDED PILOT-STUDY USING A MODIFIED PASSIVE HEMAGGLUTINATION ASSAY

Screening for hepatitis B surface antigen (HBsAg), even by the most sensitive techniques, fails to detect all carriers of the hepatitis B virus (HBV). The presence of hepatitis B core antibody (anti-HBc) in the absence of HBsAg is a common finding in donors implicated in cases of post-transfusion hepatitis B (PTHB), and viral DNA may also be demonstrated in many of these individuals. An extended pilot study of routine screening of all donations for anti-HBc in addition to HBsAg was introduced into the Mersey and North Wales Regional Transfusion Service in November 1991 to improve surveillance for carriers of HBV. In order to reduce costs a modified passive have a sensitivity of 99% and specificity of 98% compared with a conventional assay. In the first 6 months 60 530 donations were tested and 12 (0.02%) were found to have anti-HBc in the absence of HBsAg or adequate antibodies to HBsAg (anti-HBs). These sera will later be submitted for polymerase chain reaction (PCR) testing in order to determine their infectivity or other-wise by the detection HBV DNA sequences.