Prevalence of antibody to hepatitis B surface antigen among qualified blood donors in Nanjing, China

Universal infant hepatitis B vaccination has been implemented more than three decades. This study aimed to determine the prevalence of antibodies to hepatitis B surface antigen (anti-HBs) and to hepatitis B core antigen (anti-HBc) in qualified blood donors in Nanjing, China. Plasmas of 815 qualified blood donors, collected from February through May 2019, were measured for anti-HBs and anti-HBc by enzyme-linked immunosorbent assay. There were 449 (55.1%) male and 366 (44.9%) female blood donors, with a median age of 28.9 years (18–60). The seroprevalence of anti-HBs was 58.8%, with no significant difference in different genders and different age groups. The overall prevalence of anti-HBc was 7.0%, with an increasing trend with age, from 0% in 18–20 years old group to 17.9% in 51–60 years old group (χ(2) = 46.7965, p < .0001). The prevalence of anti-HBc in donors born after the implementation of universal hepatitis B vaccination was significantly lower than that in donors born before (1.0% vs 15.5%; χ(2) = 63.6033, p < .0001). Our data suggest that more than half of the blood donors in Nanjing are anti-HBs positive. Since a blood recipient usually receives more than one unit of red blood cells or plasma, passively acquired anti-HBs in blood recipients may neutralize hepatitis B virus potentially presented in blood donors with occult hepatitis B infection. In addition, the presence of anti-HBs and/or anti-HBc in blood donors may cause unique hepatitis B serological profile in blood recipients.