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Does HIV DNA PCR Test Give A Good Indication Of One's Status If One Test After 4.5 Days Of Possible Exposure?

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Posted on Tue, 2 Oct 2012
Question: Does a Hiv Dna Pcr test gives you a good indication of your status if you test 4.5 after possible exposure? I know for accurate or conclusive resluts you should wait 28 days but I've read that this test can pick up infection with 48-72 hours.
doctor
Answered by Dr. Dr. Michelle Gibson (41 hours later)
Hi

There are different tests that can be used to detect HIV.
The most commonly used screening test, the ELISA, tests the blood for the presence of antibodies which are formed when your body reacts to the presence of the virus. Because that test does not check for the virus directly, but your body's reaction to it , it has a long window period. The window period is the time it takes for a test to definately detect an infection.For an ELISA it is up to 3 to 6 months.

For the DNA test, it checks for the virus directly so the window period is shorter, it can detect HIV within a week or a few days of exposure, it still however has a window period of 21 days( some persons may have an initial negative result after a few days which may be positive after a longer period).If you think you have been exposed consider repeating the test at this point to get a final result.

I hope this helps, feel free to ask any other questions
Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar
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Follow up: Dr. Dr. Michelle Gibson (3 hours later)
Thank you for your opinion on the test, I've been reading alot of contradicting information. My possible exposure was that the guy I slept with we used a condom it's just afterwards he got up so quickly and then I went to the bathroom to clean myself up so I didn't see the condom. When I stood up no cum came out and I even checked 15 minutes later by sticking my finger up my vagina to see if anything would come out and it was just a little bit of my own cum. So I don't know if this is considered a high or low risk or not, what do you think? And do you have any idea of what the odds will be of me having a negative test after 4.5 and then it turning positive?
doctor
Answered by Dr. Dr. Michelle Gibson (6 hours later)
Hi

The fact that a condom was used reduces the risk of transmission of any of the sexually transmitted infection including HIV.
The fact that you used a condom (which reduces rate of transmission by close to 90%) and that the original test was negative would suggest that it is highly unlikely that the second test would be positive.In terms of the likelihood of your original negative test becoming positive, the data mainly focuses on the sensitivity of the test at 21 to 28 days , so an exact percentage/rate is not available, sorry about that.
HIV dna test has a sensitivity of 99 % at 21 to 28 days (high sensitivity means that there are very few or nil false negative results- if a person has it , the test picks it up)

Hope this answers your question and everything works out for you, feel free to ask anything else if not clear
Note: Get personalized answers to your HIV related queries You can choose to talk face to face with your doctor. Book a Video Call now.

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar
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Answered by
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Dr. Dr. Michelle Gibson

General & Family Physician

Practicing since :2001

Answered : 16835 Questions

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Does HIV DNA PCR Test Give A Good Indication Of One's Status If One Test After 4.5 Days Of Possible Exposure?

Hi

There are different tests that can be used to detect HIV.
The most commonly used screening test, the ELISA, tests the blood for the presence of antibodies which are formed when your body reacts to the presence of the virus. Because that test does not check for the virus directly, but your body's reaction to it , it has a long window period. The window period is the time it takes for a test to definately detect an infection.For an ELISA it is up to 3 to 6 months.

For the DNA test, it checks for the virus directly so the window period is shorter, it can detect HIV within a week or a few days of exposure, it still however has a window period of 21 days( some persons may have an initial negative result after a few days which may be positive after a longer period).If you think you have been exposed consider repeating the test at this point to get a final result.

I hope this helps, feel free to ask any other questions