Abstract: Objective To use different types of NAT method to detect the HBsAg negative repeated non-reactive (NRR) donor samples, and ELISA method to detect the relative markers of HBV DNA positive samples, so as to confirm the changes of serological infection indexes of HBV DNA positive samples and ensure the safety of blood use. Methods A total of 60 NRR samples were collected after the detection of 82 278 blood donor samples using the TMA ID-NAT. Three different types of NAT methods were used to detect HBV DNA.Methods① HBV DNA identification tests were performed three times.Methods② HBV DNA was detected with different PCR reagents A and B. Methods③ Q-PCR was used to quantitatively detect HBV DNA, and the total positive number and ratio of the three methods were obtained. ELISA method was used to detect relevant markers in the HBV NRR donor population infected with the virus, and OBI infection situation was obtained, and then compared with the qualified donor population to analyze whether there was any difference in the ratio of antibody and serological combination mode between the two populations. Results Among the 60 NRR samples, method ①19 cases (31.67%, 19/60) were detected positive for HBV DNA, method ②23 cases (38.33%, 23/60) were detected positive for HBV DNA, method ③ 9 cases (15%, 9/60) were detected positive for HBV DNA, with low viral load. A total of 32 cases (53.33%, 32/60) of HBV-infected NRR samples were detected by the three methods, including 19 cases (59.38%, 19/32) with the method ①, 8 cases (25%, 8/32) with the method ② and 3 cases (9.37%, 3/32) with the method ③ alone. The positive rates of HBcAb (+) and combination mode 1 were statistically different between the two groups. Conclusion Multi-type NAT combined detection can improve the detection rate of HBV DNA in NRR samples and increase the detection of markers, changes in the positive rate of HBV infection markers were identified in NRR donors with positive HBV DNA.

Key words: NAT NRR, HBV, Q-PCR, ELISA