Objective To analyze the HBV S region gene mutation in serum samples of occult hepatitis B virus (HBV) infection (OB1), and to further analyze the mechanism of gene mutation and OBI.

Methods Blood samples from unpaid blood donors from January 2022 to December 2023 were collected and analyzed for serology, liver function indicators, viral load and gene mutation.

Results A total of 90 OBI cases were detected, the detection rate was 0.051%, and the incidence of OBI was correlated with age. The sequence amplification of s region in the blood samples showed the presence of C type and B type genes, both of which occurred in the hydrophilic region.

Conclusion There is no abnormal liver function between OBI and hepatitis B population, and there is no difference in viral load between different serum modes. Mutations in the HBVS region are more likely to cause OBI, which provides a scientific basis for more sensitive HBV detection.

The authors have declared no competing interest.

This study did not receive any funding

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Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Ethic Committee of Jiangxi Province Blood Center gave ethical approval of this work

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All data produced in the present study are available upon reasonable request to the authors