Evaluation of HBsAg automated immunoassay results 0.5 negative

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Doctor let me ask. Before I went to donate blood, by chance the rapid test for HBV was positive, but then I had to repeat the HBsAg auto-immunoassay test again and the result was 0.5 negative. I've done that twice. What did the doctor tell me to ask? Thank you doctor.
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Hello. You do the test twice with 2 different methods, so it is not possible to confirm the results are accurate.
You need to specify the time to do the above 2 tests. If both times the results are correct, it is possible that in the first test, you are infected with the acute phase of hepatitis B virus, then the body produces antibodies against the virus and completely recovers. You can do more Anti-HBc total test to accurately assess whether you have ever been infected with hepatitis B virus or not and do Anti-HBs to evaluate the body's immune response.
You can choose a hospital under Vinmec Health System to check your health status as well as advise on the case of an HBsAg automatic immunoassay test with negative 0.5 results. Wishing you good health always.
Answered by Doctor Nguyen Thi Thuy Hang - Doctor of Microbiology - Laboratory Department - Vinmec Times City International Hospital

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