Comparative sensitivity of HBV NATs and HBsAg assays for detection of acute HBV infection
Article first published online: 21 MAY 2003
Volume 43, Issue 6, pages 788–798, June 2003
How to Cite
Biswas, R., Tabor, E., Hsia, C., Wright, David J., Laycock, Megan E., Fiebig, Eberhard W., Peddada, L., Smith, R., Schreiber, George B., Epstein, Jay S., Nemo, George J. and Busch, Michael P. (2003), Comparative sensitivity of HBV NATs and HBsAg assays for detection of acute HBV infection. Transfusion, 43: 788–798. doi: 10.1046/j.1537-2995.2003.00424.x
GSC = Genetic Systems Corporation; SC = seroconversion; S/CO = signal-to-cutoff; WB = whole blood; WP = window period.
This work was supported in part by the FDA and the National Heart, Lung and Blood Institute's Retrovirus Epidemiology Donor Study (REDS), under the auspices of the REDS NAT Study Group. BioClinical Partners contributed HBV seroconversion panels and test manufacturers contributed reagents or performed assays at no charge to the study.
- Issue published online: 21 MAY 2003
- Article first published online: 21 MAY 2003
- Received for publication September 24, 2002; revision received February 19, 2003, and accepted March 15, 2003.
BACKGROUND: A study was designed to estimate relative analytic sensitivity and window-period (WP) closure and to project incremental yield of newer HBsAg tests, pooled-sample NAT, and single-sample NAT, compared to currently licensed HBsAg tests.
STUDY DESIGN AND METHODS: HBV DNA and HBsAg test results for 23 HBV seroconversion (SC) panels were first analyzed to construct a model of primary HBV viremia. One-hundred representative samples were then selected from 10 panels and coded with 28 analytical controls. All 128 samples were tested by seven HBsAg tests and by four pooled-sample and three single-sample NAT assay formats. Results were analyzed to obtain differential times to HBV detection and combined with HBV incidence rates to project comparative yields.
RESULTS: HBV doubling time during the ramp-up phase was estimated at 2.56 days. HBsAg concentrations at cutoff for new tests ranged from 0.07 to 0.12 ng per mL, compared with 0.13 to 0.62 ng per mL for licensed tests. Estimated viral load at cutoff ranged from 102 to 267 IU per mL for new tests and from 363 to 1069 IU per mL for licensed tests. HBsAg tests detected 31 to 63 percent of early ramp-up phase samples in the 100-member seroconversion panel study, while pooled-sample NAT detected 55 to 71 percent and single-sample NAT, 82 to 99 percent. Compared with currently licensed HBsAg assays, newer HBsAg assays would reduce the WP by 2 to 9 days; pooled-sample NAT would reduce the WP by 9 to 11 days; and single-sample NAT would reduce the WP by 25 to 36 days.
CONCLUSION: Newer HBsAg tests would be expected to detect an additional 15 to 21 infected units per 107 donations, compared to licensed HBsAg tests. Sensitivity, WP closure, and yield projections for newer HBsAg assays and pooled-sample NAT are comparable. Single-sample NAT would increase yield by 13 to 15 units per 107 donations over pooled-sample NAT and newer HBsAg assays and by 35 to 50 units per 107 donations over currently licensed HBsAg assays.