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HIV duo after 35 days


HIv antigen-not determinable,
What is the interpretation ?
what does not determinable means



Thank you for your inquiry. From what we gather from the question, you were asking about the meaning of a 4th Generation HIV "duo" test that has an antibody value of 0.02 and an antigen value of "not determinable".

"Not determinable" represents an invalid test in which the value cannot be calculated. There are a variety of reasons for this result, but since the antibody value of your test represents a negative test, it is likely that the value for the antigen is below the testing threshold. The results of a 4th Generation HIV "duo" test are considered conclusive by most HIV specialists 6 weeks after exposure. Some guidelines and physicians recommend retesting 3 months post-exposure for completely conclusive results. Although it is very likely that you do not have HIV, due to the negative antibody result, you should get retested outside of the window period, since 35 days (~5 weeks) is within the window period, for completely conclusive results.

Recommendation: Refer to a physician for an HIV test 6 weeks and 3 months post-exposure for completely conclusive results.


AIDS Vancouver Helpline/Online, Marie