Detection of HBV DNA with full automatic system and HBV genotyping in blood donor screening

Objective To establish fully automated sample pooling, nucleic acid extraction, amplification and detection method for HBV DNA testing, and investigate the seroconversion and genotype in HBV DNA positive donors. Methods Individual donor plasma samples serologically negative for HBV were pooled by STAR2000 sampling processor with a size of 24. Nucleic acid were automatically extracted by MPLC simultaneously, amplified and detected by Roche COBAS AMPLICOR system. The sensitivity of detection was determined by international standard. HBV DNA positive donors were genotyped and followed up by serological tests. Results The 95% detection limit for this automated HBV DNA testing system was 38.9IU/ml,with 95% confidence interval (21323),eight out of 16512 specimens were PCR positive for HBV DNA,with a positive rate of 0.049%. Three of the 8 DNA positive donors were genotype C,2 genotype B, 1 genotype D,and the other 2 uncertain。Six of the eight HBV DNA positive donors were followed up, and three of them seroconverted。 Conclusion Fully automated HBV DNA detection method can be applied in blood screening,and will further increase the safety of blood supply.