[Question #361] HIV Risk and Oraquick Oral Swab Test

35 months ago
Hi Doctors,

I had brief (2 mins) unprotected vaginal sex with a girl from Backpage.  Don't know if she uses protection regularly or uses drugs.  I myself am heterosexual male, not an IV drug user and have never had anal sex.  I took the Oraquick Oral test 10 weeks and 2 days post exposure and it was negative.  Also, I know you always say symptoms are NOT a good way to check status, but is the absence of symptoms helpful?  If 40-70% of newly acquired infections develop some combination of the 3 main symptoms, I would assume not having them says something.  I haven't had any ARS symptoms and I've been monitoring my temperature every few days.  No rash, no sore throat either. 

I've also been tested for Chlamydia and Gonnorhea and both were negative.  I didn't get a Syphilis test as the clinic I went to for the bacterial STDs wouldn't give it to me saying I was too low risk.  I did have a test done 6 months ago which was negative (from the same clinic, but I guess they changed their policy recently). 

My Questions:

1. Can I reasonably conclude that I'm HIV negative after the 10 week result?  I know 12 weeks is the date, but I don't really have the means at the moment to get another test. 

2. Regarding Syphilis, I have not had the chancre appear and I've been pretty careful to check.  Do you think I should test elsewhere for it? 
35 months ago
One thing I forgot to add, I purchased two of these Oraquick test.  There was a problem with the first one so I discarded it and used the second one 15 mins later.  I talked to the reps at OQ and asked them if using back to  back tests would affect the results (maybe too small a sample is collected on the 2nd swab) and the rep I spoke with said no, but I don't know if they fully understood my questions.  Do you know if this would affect my 2nd test result? 
H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
35 months ago
Welcome to the forum. By chance I logged immediately after your question came in. Most users shouldn't expect nearly real time replies!

This was a low risk exposure in regard to HIV, both because of the low chance such a woman has HIV and the relative rarity of transmission by vaginal sex. Both of these odds probably are on the order of 1 in a thousand, so mathematically the chance you caught HIV is in the ballpark of one in a million -- i.e. very strongly in your favor. Symptoms don't help much in either direction. I would agree that absence of symptoms means "something", but it's an awfully small something. With the chance you were infected in the range of one in a million, perhaps you'll agree that an additional 50% reassurance, making the odds one in 2 million, doesn't contribute anything of importance.

I'm glad you were tested for gonorrhea and chlamydia. The odds of these, especially chlamydia, was much higher than for HIV or syphilis. But your negative test results are reliable, so you're home free for those infections.

To your specific questions:

1) Of the many HIV tests generally available in the US, the oral fluids test is the only one that sometimes takes 3 months to be conclusive, so 10 weeks was a bit early. However, I would estimate it would pick up ~95% of infections by that time. If I were in your situation, I wouldn't test again. But if you need to reach that 100% mark, you'll need another test.

2) The chance of syphilis is almost as low as for HIV, since a) the large majority of syphilis in the US these days occurs in men having sex with men, with only rare infections in women or in heterosexual transmission; b) absence of symptoms (chancre) which usually is obvious when the penis is the exposed site; and c) the clinic's true statement about how low your risk was.

I hope this has helped. Best wishes and stay safe--   HHH, MD


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H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
35 months ago
Your follow-up comment came in while I was writing the reply above. There is no way that mis-collection of one specimen had an adverse effect on specimen quality or test reliability a few minutes later.

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35 months ago
Thanks Doctor!  I guess I had just one last question/comment...

A 5% chance seems small, but it's kind of relative.  5% chance to win the lottery seems impossible, but  5% chance of my test being inaccurate (too soon) seems still rather significant.  I know my only option is to get another test post 12 weeks to be 100% sure as you said. 

To put things in perspective, if you were a betting man, is the better bet that my test would turn positive after 12 weeks or that I'd be hit by a light blue honda accord with a license plate ending in 6 as I'm crossing the street on Saturday at 4pm. 

I know it's a dumb question, but I just thought I'd throw it out there to gain perspective.    
H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
35 months ago
You misunderstand. There is nowhere near a 5% chance of your test being inaccurate. As noted, before you even get tested, the odds you have HIV are in the range of one in 2 million. 95% reliability of your negative test reduces that to around 1 chance in a hundred million (0.0000005 x 0.05 = 0.00000000125). Your calculated odds of being positive probably are much too high.

To maybe put that in perspective, the National Safety Council estimates the odds the average American will die in a traumatic accident (auto wreck, drowning, fall, etc) at one chance in 1,756. That's thousands of time more likely than the chance you have HIV. But as I said, you are free to test yourself again if you wish. In the meantime, do your best to stop worrying. And don't forget your seatbelt.


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