Hepatitis B virus DNA in serum of 'anti-HBc only'-positive healthy Lebanese blood donors: significance and possible implications.

Transmission of HBV infection through transfusion of HBsAg-negative blood has been documented. It is evident that low levels of HBV-DNA remain detectable in serum and liver tissue of some patients who clear HbsAg, and that the detection rate is highest in individuals who are 'anti-HBc positive alone'. This study was designed to assess the frequency and clinical significance of 'anti-HBc alone' in Lebanese blood donors. A total of 5511 blood donor samples from three major hospitals representing most regions of the country were tested for anti-HBc, amongst other screening tests. Samples positive for 'anti-HBc alone' were then tested for HBV-DNA and any positive for HBV-DNA were then genotyped and investigated for hepatitis B viral load. The study showed that 203 (3.7%) of randomly selected Lebanese blood donors were confirmed as 'anti-HBc alone'. Of these, 11 (5.4%) were HBV-DNA positive as detected by nested PCR. All samples had HBV-DNA levels below 400 copies/ml and all were genotype D. It can be concluded that HBV was present, although the circulating amount of virus was below the detectable limit for the assay used. Therefore, routine screening for anti-HBc may be required in Lebanese blood donation centres as an additional preventive measure for controlling transmission of HBV via blood transfusion.