[Question #1735] HIV Testing

43 months ago
Hello Doctors
I had a p24/4th generation test done and it came back negative. This was 6 months post possible exposure. All other tests were negative too(herpes, chlamydia, etc). I was wondering if these results are conclusive? Especially the HIV test. I has just a hereselect test done 3 weeks later and I had an equivocal result for hsv 1. If the hiv test missed my infection could pseudotype HIV 1 and HSV 1 happen. I guess my question is can having HIV cause a possible positive HSV 1. I've read that the 2 viruses interact at the cellular level. Do you have any insight on this? 
H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
43 months ago
Welcome to the forum. Thanks for your question.

HIV:  The modern HIV blood tests are among the most accurate diagnostic tests ever developed, for any medical condition. The results are 100% reliable if done sufficiently long after the last possible exposure, which varies from 4 weeks to 3 months, depending on the particular test or combination of tests. For the p24 antigen-antibody (4th generation) test, that time is 4 weeks. Your negative result at 6 months proves you do not have HIV, assuming no exposures more recently.

Non-herpes tests:  Assuming you had a urine or urethral swab specimen for gonorrhea and chlamydia, those results are conclusive any time more than 3-4 days after exposure. (But if you were only tested at 6 months, it is conceivable that you had either of these, with a spontaneous cure by the immune system before testing. Even without treatment, virtually all gonorrhea and most chlamydia is cleared by the immune system within a few months.) Syphilis blood tests are conclusive at 6 weeks and beyond. If your test panel included tests for viral hepatitis, those would be conclusive after 6-8 weeks.

HSV:  Probably you have HSV1; most equivocal HSV1 results probably are really positive. In the absence of symptoms typical of genital herpes, most likely that result reflects a distant past oral infection, perhaps in childhood. As for HSV2, a negative result at 6 months is conclusive. It is true that some of these viruses interact with one another at a cellular level, but this has no effect on blood test results. Having one STD (HIV or any other) has no effect on the reliability of tests for any of the others. Even if you had HIV, which you don't, it would have no bearing on your equivocal HSV1 result.

I hope these comments are helpful. Let me know if anything isn't clear.

HHH, MD

---
43 months ago
Okay thank you for your help. Why did my doctor say it can take years for antibodies to develop for HIV? I know you are an expert in the STD field  I just don't understand why my doctor told me that. Also, I had my tests done through Quest Diagnostics. Should I worry about lab error/technician error with them? My anxiety is at an all time high thinking that the lab made an error. I just am having a rough go after having these tests done and accepting the results. Does hsv 1 genitally usually have an initial outbreak? I've no recollection of having a cold sore on my genitals or mouth. Not knowing if I have genital hsv 1 or oral is driving me crazy and I know there is no way to know where it is until I have an outbreak. What should I tell my girlfriend about my hsv 1? Should I say it could be either or both? Your forum has been a great help. What you and the other doctors do  is a great service so thank you for that. 
43 months ago
Something that may help to distinguish if my hsv 1 is oral or genital....I had vestibular neuritis back in October. I know that is usually caused by hsv 1 but does it matter if it's genital or oral. I've read that where it is in the body is typically where it stays. I had this a week after taking a breathilizer from a DUI checkpoint. Sorry for replying before you had a chance. 
H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
43 months ago
Here is my standard reply to questions about differences between our advice about HIV test widow periods and other sources, especially CDC whose official advice still says 3 months. Nobody who understands HIV and the modern, routine tests -- and I mean nobody -- says more than 6 months is necessary. Your doctor is simply wrong, or you misunderstood.

CDC developed its advice before 4th generation tests became available. The first reason is that many government agencies generally take conservative positions on prevention advice, and 3 months does that. Second and perhaps most important:  As a government agency, CDC's advice usually must be consistent with the official information provided by the test manufacturers in the tests' package inserts. That information is based on original research, before the tests were marketed, and much of that research is conducted in a way that probably underestimates the tests' true performance. In any case, that information cannot legally be changed unless and until the test manufacturer conducts and new research to justify the change, and that research is vetted and approved by the US Food and Drug Administration. That's a very expensive process and therefore is rarely done. Other research, or the clinical experience of experts using the tests in the real world, and theoretical considerations about how the tests work may not be used to justify a revised package insert or any other information provided to the public. However, independent experts do not have those restrictions and can give advice based entirely on their clinical experience and their interpretation of the science of the tests and published science. That's what we do on this forum.

As for lab error, it is extraordinarily rare in HIV testing. I haven't heard of this occurring for over 20 years. Most important, the tests are highly automated:  there is almost nothing a lab tech can do to screw it up.

Saying anything to your girlfriend about HSV1. Half of all adults in the US (more in some countries) have positive HSV1 blood tests. In absence of an obvious outbreak (oral herpes i.e. cold sore, or genital), transmission is rare. Few peoplle with positive blood tests without symptoms ever infect anybody. Also, HSV1 probably is never transmitted by breathalyzer or similar exposures. Almost certainly you were infected long before that event. Finally, you have misunderstood something you read about vestibular neuritis:  HSV is an uncommon cause.

---
43 months ago
So with your expertise, would you advise I keep my hsv 1 status to myself? No symptoms that I can remember. Whether this infection be genital or oral I don't need to disclose this information to my current partner? Because of the low transmission rates when no outbreak has ever been present. I know this virus can be shed asymptomatic. I plan on marrying this woman I'm with and having babies. I know neonatal herpes is serious. I'm just worried I could cause that because the possibility of it being genital. I was only tested because I never had been before and have had multiple partners. Which I know is a good thing I was tested but this hsv 1 thing has me so worried and anxious. 
43 months ago
Last questions. Sorry I forgot to add these. Could my hsv 1 be actually negative? Since it was only .95 equivocal. If so what could cause that? If I was exposed younger, wouldn't I have more antibodies? 
H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
43 months ago
As I said above, most equivocal HSV1 blood tests turn out to be truly positive. However, with an ELISA index of only 0.95, I would guess there's a 50:50 chance you have it. You could be retested to see if it changes. But since it really doesn't matter one way or the other, if I were in your situation, I wouldn't do it. (By the way, I've been HSV1 positive for at least 50 years. No worries for me or my family.) There are no medical or health explanations for uncertain results; it appears to be random.

You are a poster child of why public health experts recommend against testing people without symptoms for HSV.  You are serious overreacting to an everyday, unimportant fact about yourself. As I said, half of all adults have HSV1. Most don't know it. You are no more at risk to your wife or anyone else than you were in the past 20-30 years before you knew. Have you infected anyone? Most people would probably tell their wives, not so much because of infection risk but because couples usually discuss such things. And since you're so over the top anxious about it, it would probably do you good to get it off your chest with her. So it's up to you. As for asymptomatic shedding, looks like you didn't read or understand my comments above:  yes it occurs with HSV1, but not often and usually in small amounts, and transmission depends mostly on overt sores. (Very unlike genital HSV2 in this regard.) As for infecting your kids, every year we can estiamte that 2-3 million babies in the US are born to parents of whom one or both have HSV1. Yet only a very small handful of HSV1 infected babies each year, and those mostly from newly acquired genital infection.

Anyway, all this is so unimportant. Just let it go and stop worrying about it.

That completes the two follow-ups and replies included with each question, and so ends this thread. Take care, stay safe, and stop worrying.

---