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HIV Ag/Ab tests

Question: 

I had sex with 5 escorts within the span of one year (2015-2016). I am not sure about the condom breakage . For past one year (2017-till now ) i have been getting sore throat swollen lymph node and fevers , mouth sores and body aches cold sores ( 2-3 times in a month) , headcahes , dizziness and a stiff neck . I took 9 oraqucik tests( July - septmeber) 4 blood tests HIV AG/AB with reflexes ( July - september) all came back negative not sure what's causing these symptoms should i trust my test results and go ahead with my life or any other tests recommended ? And can you please shed some knowledge on HIV AG/AB tests will the antigens and antibodies be detected for the whole life if infected ? And also what are the factors that don't cause HIV antibodies in the body ? I dont have any auto immune disease my blood work( Liver tests , CBC , other STD's came back normal and fine .

Answer: 

Hello,

Thank you for your inquiry. From what we gather from the question, you were asking about the accuracy of the results of negative OraQuick and HIV Ag/Ab tests with reflexes tested outside of the window period.

Any test that is not conducted in the laboratory, such as OraQuick for at home testing, has a larger margin of error than tests conducted by laboratory professionals (1). An HIV Ag/Ab test provides extremely accurate results (99.9%) in the diagnosis of HIV-1/2 (the two main types of HIV) after 6 weeks post-exposure (1). Any positive result from the initial HIV Ag/Ab test will be re-tested with other confirmatory tests to validate the result. Refer to the flow chart below from AIDSinfo for a understanding of typical HIV testing strategies (2).

HIV Testing Flow

In the case of HIV Ag/Ab with reflexes, the reflexes are the confirmatory tests. Confirmatory tests may be performed if the patient has had a high-risk exposure or if the initial HIV Ag/Ab test came back positive. Laboratories perform confirmatory tests to determine whether or not the initial result of the HIV Ag/Ab test is a rare (0.5%) false positive (1). Since the confirmatory tests you received produced a negative result, it is extremely unlikely that you have an HIV infection. Please note that depending on the region you are in, the confirmatory tests may only test for HIV-1 using a Western Blot, as it is much more common than the extremely rare HIV-2 (<1%), which is mainly only seen in a few West African countries (3).

Antigens (Ag) of the HIV virus are typically only detectable at the initial stages of the infection (2-6 weeks). After this period the antigen is no longer found at high levels in the blood, but the antibodies (Ab) are now present and will be detectable for the rest of your life. The purpose of having a test that evaluates the presence of both the antigen and antibody is to detect early infections as well as later infections.

Recommendation: Refer to a physician for more personalized answers.

Regards,

AIDS Vancouver Helpline/Online, Marie