Value of retaining HBsAg donor screening where HBV NAT and anti ‐HBc donor screening apply

Hepatitis B virus (HBV) is a transfusion‐transmissible human DNA virus with a global distribution. Since the early 1970s, hepatitis B surface antigen (HBsAg) detection has been the mainstay to identify donors infected with HBV. The implementation of donor HBsAg screening substantially reduced but did not eliminate the risk of transfusion‐transmitted HBV (TT‐HBV). In the late 1970s, it was recognized that TT‐HBV occurred more commonly from HBsAg‐negative donations containing detectable antibodies to the viral core (anti‐HBc) leading to some countries subsequently implementing universal anti‐HBc screening in addition to HBsAg. Since the late 1990s, HBV nucleic acid tests (NATs) have been applied to donation screening to ‘close’ the acute window period, thereby reducing the residual risk of TT‐HBV. Their implementation also identified HBsAg‐negative/anti‐HBc‐positive individuals with detectable HBV DNA, a novel pattern of infection termed occult hepatitis B infection. A number of countries now combine HBsAg, anti‐HBc and HBV NAT donation testing, which provides the opportunity to determine the proportional HBV risk reduction contribution of each test. The cumulative published data indicate HBV‐infected donors with HBsAg as the only marker are exceedingly rare, occurring at a rate of about 1 in 4 million in the largest published study. There are no recorded cases of TT‐HBV involving ‘HBsAg‐only’ positive donors. Ultimately, HBsAg testing reta...
Source: ISBT Science Series - Category: Hematology Authors: Tags: Congress Review Source Type: research