HIV test

[joescare]

Dr. Handsfield,

I have a AIDS phobia. Im almost getting crazy...
I have taken HIV1/HIV2 combo abs EIA and HIV-1 RNA UPCR test 26 days after potential exposure.
All result were negative. I would like to ask some questions about these tests. HIV-1 RNA QNT PCR was not done since the result was lower than 1.7. I met a pediatrics doctor in student health center and she said theere is no way to detect before 90 days. I made me really confusing.

1) what is window period for the EIA and PCR tests? WHO says window period is from 14 to 21 for antiobody test. Is that correct?
2) How much percent are the results reliable after 26 days test? I read PCR test after 20 days almost can confrim negative,and newest EIA test can confirm 98% after 4weeks. is it true?
3) Can I confirm after 6 weeks with EIA test?
4) What is difference between EIA and ELISA test regarding window period and accuracy?
5) I have taken the test from ARUP laboratory in SLC, is the EIA fourth generation?
6) How much am I safe now???
thanks,

[notAnExpert1]

Dude! You dont need HIV test you need to see a shrink. and I dont say that as a joke, seriously. You cant freak out like this every time you have sex for the rest fo your life

[H. Hunter Handsfield, M.D.]

Good grief.  Read my other replies.  If you cannot live with a 199,999,999 out ov 200,000,000 assurance that you don't have HIV, I cannot help you.

This thread is over.

[joescare]

"But now factor in 99% reliability of the test results you have had."
Does it mean I have only 1% risk after 6 weeks test?
Is it true PCR test after 4weeks is 99% reliable?
If so, I can be really relax with those results. In the statistics, 1% is not happeing.

thanks so much

[H. Hunter Handsfield, M.D.]

Thanks to o_g for that clarification.  The site says the window period is "normally" 14-21 days, but "normally" isn't defined; it might mean only 80-80% of people.  For advice on this forum, I'll continue to use ~90% by 3-4 weeks and ~99% by 6 weeks.

[H. Hunter Handsfield, M.D.]

Sigh.  Another person with a wildly unlreasltic, pessimistic understanding of the risk of HIV from heterosexual sex.  Chance your partner had HIV (even if highly promiscuous, but not a sex worker or injection drug user), 0.1% (1 in 1000).  Chance you got infected from a single episode uf unprotected vaginal sex average 1 in 2000.  That means your actual risk of catching HIV was 0.001 x 0.0005 = 0.0000005, or 1 chance in 2 million.  You did not need HIV testing at all on the basis of that exposure.  Do you think every person after every episode of unprotected sex with a new partner needs to go out and get HIV tested?  That happens millions of times a day; the medical system couldn't handle the load!  But now factor in 99% reliability of the test results you have had.  That makes the current chance you have HIV 1 in 200 million.

Forget it.

[o_g]

Sorry to post in this thread but WHO indeed says window period to detectable antibodies is 14-21 days. Here is the official link:
http://www.who.int/diagnostics_laboratory/faq/window_period/en/index.html

[joescare]

Please, just one question. I had sex with unknow girl and condom was taken off. Im so worried aobut it.
You said 2) Those results mean you don't have HIV. Does it mean we can confrim that Im clear, otherwise how much percent it is reliable?
I will finish after 6 weeks test. Can I conrim with that 6 weeks test? Im pretty healthy normal person, didnt have any disease or immune system problem.

[H. Hunter Handsfield, M.D.]

Users of this forum are responsible to review the forum to see previous replies to similar questions before they post their own.  See the prominent notice above:  "If you have not done so, please review other threads in our archives for questions similar to yours and Dr. Handsfield's replies. Questions that duplicate other frequent ones, for which abundant replies exist, and that have little educational value for other forum users, will be DELETED WITHOUT RESPONSE. YOUR PAYMENT WILL NOT BE REFUNDED."  Use the search linik; or just review any 15-20 threads at random.  The time for tests to become positive is the single most common topic on this forum.  So my answers are very brief.

1) I think you are quoting WHO on the PCR test.  Modern EIA (antibody) tests take 4-6 weeks.

2) Those results mean you don't have HIV.

3) Sure, test again at 6 weeks with (another?) EIA if you like.

4) EIA (enzyme immunoassay) and ELISA (enzyme-linked immunosorbent assay) are different words for the same thing.

5) I don't know what ARUP means.

6) How safe you are depends on more than the test result.  It also depends on your sexual lifestyle and the nature of the exposure(s) you are concerned about, and you say nothing about that.  Read innumerable other threads to learn more.

No follow-up questions, please.

HHH, MD