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A member asked:

Testing for hbsag can give false positive after vaccination. is it the case with hepatitis b pcr also? does vaccination affect dna pcr result also?

A doctor has provided 1 answer

Hepatitis B antigens: Positive hepatitis B antigens found in the blood are sign of infection, but antibodies to the antigens are signs of protection. Other antibodies are found in the beginnig of the infection. The vaccination is very good, but someindividual might not respond or might need repeat vaccination.

Dr Hodge agreed

Answered 5/19/2016

3.6k views

Thank

Related Questions

A member asked:

Hepatitis b blood test shows both anti-hbs (i was vaccinated 13 years ago) and hbsag. Does that mean i was recently exposed or that I am chronic?

3 doctors weighed in across 2 answers

A member asked:

Exposure:oral sex(protected):all negative tests -HIV 4THGEN.@63,72&78days -VDRL@57,72&78days -TPHA@35,40&45days -urine pcr(for 7 stds)@4,14&38days. -HBV antigen(i am vaccinated for hepatitis B(72&78days) -HCV(72&78days) Are these Tests conclusive?

5 doctors weighed in across 2 answers

A member asked:

Which additional tests do I require to be diagnosed with hep b? Last year i got HBsAG positive, DNA HBV negative results. Which other markers of HBV tests should I be tested for to know whether I am a carrier and can infect others?

2 doctors weighed in across 2 answers

A member asked:

Can a Pfizer covid vaccine given 1 week after risk exposure give false negative test results for syphilis and hepatitis b 12 weeks after risk exposure? Syp. RPR + WR test Hep. B. Hbsag + Hbsab Will body always produce enough ab and ag at 12 weeks?

4 doctors weighed in across 3 answers

A member asked:

I am fully vaccinated with Pfizer. I had a potential exposure three days ago. Could a PCR test give me a false positive in that I fought it off but still show positive? Could a rapid antigen test give me a good idea if I was positive at this point?

A doctor has provided 1 answer

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