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Dr. SH
Dr. SH, Board Certified Physician
Category: Medical
Satisfied Customers: 8770
Experience:  Doctor of Medicine
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Can i ask how accurate a combo antibody and antigen blood

Resolved Question:

can i ask how accurate a combo antibody and antigen blood test that came back negative is, 18 days post potential exposure?
Submitted: 1 year ago.
Category: Medical
Expert:  Dr. SH replied 1 year ago.
Thank you for your question.
18 days is a little too early.
This test is at its most accurate at least four weeks from the exposure.
Let me know if you have more questions.
Please rate me by clicking on one of the rating options at your end as that is the only way I am credited on here for helping you out.
Kindest regards
Customer: replied 1 year ago.
I know its to early for a conclusive result but the 4 week guideline is for 95 percent plus accuracy. so could it still be pretty accurate at 18 days? as the test looks for both p24 antigen and antibodies. when i look online it says the antibodies are usually detectable by 28 days but the antigen is normally dedectable from 2 weeks. So would this mean the antigen would likely show up if there was an infection?
Expert:  Dr. SH replied 1 year ago.
Yes it is very reassuring to have a test come back negative even at 18 days.
I agree that the antigens are usually detected around two to three weeks time so it would be fairly accurate at this stage even.
So a negative test, like I mentioned, is very reassuring to say the least.
Let me know if you have more questions.
Please rate me by clicking on one of the rating options at your end.
Kindest regards
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