Trends in hepatitis B surface antigen (HBsAg) prevalence in volunteer blood donors in Connecticut, 1973-1983.

A total of 1,573,769 blood donations from volunteer blood donors from Connecticut were tested for Hepatitis B Surface Antigen (HBsAg) from 1973 to 1983. The prevalence of HBsAg decreased over this 10 year period among first time as well as repeat donors. This decrease was much more pronounced in the first three years of the study (1973 to 1975) in repeat donors. Thereafter, prevalence was stable. In first-time donors, the largest decrease also occurred in the first three years. In contrast to repeat donors, however, marked fluctuations in the prevalence were noted in first time donors. As has been the case in previous studies, HBsAg prevalence in first-time donors was significantly higher than that observed in repeat donors. Our study encompasses the longest period of observation in comparison to previous reports on HBsAg prevalence among blood donors. While it has been previously established that a decrease in prevalence over time does occur among repeat donors, stabilization of prevalence after an initial reduction found in our study has not been previously documented. This may indicate an irreducible minimum prevalence rate in the repeat donor population. In addition, our study for the first time convincingly demonstrates a reduction in prevalence in first-time donors which may reflect better communications at the donor recruitment and nursing level.