INSTI TEST NEGATIVE AT 5 WEEKS

Hi

I had a high risk exposure 5 weeks ago.

I had a negative INSTI test at both 4 weeks and 5.5 weeks.

How reliable is this?

The only symptoms I have are: enlarged lymph nodes in neck and groin and now a rash started 1 day before 2nd test.

Thanks

[kenzorio]

It is of course positive that you have tested negative so far, but unfortunately it takes 3 months for the tests to be conclusive. I'm not aware of studies showing how much value this particular test has after 4 and 5,5 weeks however the "instant" tests are in general not as sensitive as the standard blood/lab HIV tests. In particular the 3rd or 4th generation tests are very sensitive. It is very likely such a test would be positive at, say, the 6 week mark if you indeed were positive. If you want peace of mind now, take a 3rd generation blood test (if in U.S.) or a 4th generation (if in EU). If it is negative it is very likely to stay that way if you have no more risk. Still do another test (which could be an instant test) at 3 month to get a conclusive result.

[confusedandguilty]

Yesterday, I visited STD clinic in Toronto (Hassle free clinic) one of the best here. The doc said,  in theory, the window period is 3 months, but with the INSTI rapid test 6 to 8 weeks is good enough.  So i guess INSTI is more sensitive... that's what they use here in Ontario.

[Teak]

http://www.biolytical.com/hiv101.html

Standard HIV tests look for HIV antibodies, which are cells the body makes after HIV enters the blood. It can take up to three months to make enough antibodies so that they will show up on the test, although in most cases, infection can be detected in four weeks. If an infected person tests too soon during this "window period", the HIV test may not find infection, but the person can infect others.

Your doctor gave you incorrect information.

[kenzorio]

While I don't know the specific test, the Rapid/Quick/Instant tests are known to be less sensitive in general and has a longer window period compared to more advanced tests. For instance, the 3rd generation HIV antibody tests look not just for IgG as the previous generations but also for IgM which is rises before the IgG. Additionally, the 3rd generation looks for a greater set of antibodies. The 4th generation goes further than that and also looks for p24 HIV antigens which are also present before the antibodies. If you are interested, you can look up the specifications for the INSTI test to see if it tests for IgM and p24 antigen.

As Teak said, since most people seroconvert before 3 months a negative result is still reassuring as long as one doesn't "rely" on this result and still takes a test at 3 months for a conclusive result.

[confusedandguilty]

"most cases, infection can be detected in four weeks. "

that's what we are talking about... 5 week negative is good....
as Dr Sean says, trust the clinic you go to....  afterall he is a doc who told me 6-8 weeks is good enough.... I would relax if I am tested negative at 6-8 weeks