please help - confusion regarding testing

I know that during the period of acute infection, doctors will sometimes test for the virus itself, because viral loads are very high at this time.  My question is, do tests outside of the time of acute infection that test for the virus (ie pcr, antigen tests, nucleic acid testing, etc) work outside of the period of acute infection?  If I were to have one of these done 3 months after exposure and it came back negative, would that be reliable even though the viral loads would have significantly decreased at this point? Thanks!

[scared_25]

I would argue that PCR RNA tests work better sooner and more so during ARS.  As CDC states:

"Another type of test is an RNA test, which detects the HIV virus directly. The time between HIV infection and RNA detection is 9-11 days. These tests, which are more costly and used less often than antibody tests, are used in some parts of the United States."

http://www.cdc.gov/hiv/topics/testing/resources/qa/be_tested.htm#wait

But RNA (viral loads) can become not detectable in some (meaning not many) cases when the body finally fights back.  But on the other hand PCR DNA tests are best used from 28 days on, but as early as 2 weeks, b/c these levels will not become none detectable over time.

So in short less then a month or during ARS, PCR RNA tests is best, but after a month a PCR DNA test would be best, but at this point an Elisa test would work just as good and without the risk of false positive which would make most people here go crazy.

Other things I have learned since I am trying not come here as much anymore is any generation (2nd,3rd,4th) Elisa are just as accurate after 6 weeks.  This from talking with Ma., Aids Hotline, and Home Access.  Only +/- a few days after 6 week mark.

I would like to point out that I got an RNA test done at 2 weeks and if we are worried now, does it even help?  If you think it will take it, but I bet you will still question it since it is not considered a diagnostic test.

[mike_no]

Well, you are wrong at a few places, let me tell you;

1. PCR (NAT) tests directly look for the virus in the body unlike the Antibody test which looks for the body's response to the infection

2. PCR tests can tell you if your body is infected as early as 72 hrs after the exposure

3. PCRs are not for diagnostic purpose, a standard antibody test is (EIA / ELISA / ELFA) however doctors may order for NATs if they feel that one is going through ARS since it enables appropriate treatment by early detection of the virus

4. On the contrary to what you believe 'PCR can only detect the virus when one's going through ARS',PCR can can detect the virus as early as 72 hrs after the infection and the detection just keeps getting better along with the time since the HIV virus replicates itself in millions every day which means viral load keeps increasing every single day after the infection hence practically a PCR at 3 months after the exposure simply means 'No HIV'  

[mike_no]

That's a very useful information :)

Scared, I have not specified any type of PCR above and my comments were in general about 'NAT tests'

[scared_25]

That is true you did not specify the type, so I am sorry.