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Risk when condom fails with HIV + man

Feb 11, 2009

Dr. Bob: I recently had sex with an HIV positive top man, we used a condom but it broke. I read in one of your answers that the risk of transmission per episode of anal intercourse with a positive person is 6.5 per 10000 episodes. Does this risk change if the HIV neg is either the top or the bottom? I started taking antiretrovirals 2 hours after the intercourse, and I am still taking them. Does this affect the results of the screening test? Besides, I understand that PCR is not the screening test of choice. But, If I want to do it, what do you think? Is the result gonna be affected by the ART? Thanks a lot for your answer.

Response from Dr. Frascino


The estimated statistical risk of acquiring HIV from unprotected receptive anal sex with the insertive partner confirmed to be HIV positive is 50 per 10,000 exposures. (The 6.5-per-10,000-exposures statistic referred to unprotected insertive anal sex when the top (insertive) partner is negative and the bottom (receptive) partner is confirmed to be positive.)

Regarding your second question, yes, PEP can affect PCR tests. (See below.)

Dr. Bob

Please help me Dr. Bob, please PCR/PEP (PCR TESTING WHILE TAKING PEP) Sep 18, 2008

Dear Dr. Bob, First of all i just want to give you my deepest respect and thanx for this great service. You are an amazing person and an inspiration to me. I have spent a lot of time on this site in the last month...

Why... Dr. Bob, (long story short) a month ago i had (vaginal only) sex with a friend. She is HIV positive. We used a condom, but is failed completely and intercourse was finished. Ah, doc, i know it is stupid, but we were both going through a hard time and we have allways been there for each other, even before she got the HIV. It was certainly not planned, but we were careful none the less, unfortionately the precaution failed us. She is not taking any meds and i have no idea on VL's etc. I went to my doc and started taking PEP (Aspen Lamzid & Stocrin) within 21hours. I finished my last dose today. I however took a laboritory PCR diagnostic test at 19 days post exposure. The result was negative and i thaught this was at least a little whoo hoo moment, but after what i have been reading it seems that the PEP could influence the result, even though my doc told me the meds will not have any effect on the test... What is your opinion on this doc? Secondly, what if i do get infected after taking the PEP? Will this increase the risk of drug resistence?

Thank you for taking some of your valuble time to answer me.

Best regards from south africa. Ps. i am coming to the states soon for a short holiday? Can i meet you please? I am not trying to flatter you, it would just be an honor.

Response from Dr. Frascino


Yes, PEP (post-exposure prophylaxis) can affect PCR test results. PEP is a combination of antiretroviral drugs used in exactly the same dosage that we use to treat active HIV infection. Therefore, these drugs can inhibit HIV replication and drive HIV plasma viral load (PCR RNA) down to undetectable levels, thereby giving a "false negative" result if PCR RNA testing was being used for diagnostic purposes. I'll repost some information from the archives that shows this problem comes up fairly frequently. It's another reason I recommend all folks who have had an HIV exposure significant enough to warrant a course of PEP be followed by an HIV specialist physician. HIV specialists understand the limitations of HIV-related tests and are best at managing all issues related to PEP and HIV testing and at evaluating symptoms that may arise during PEP.

Regarding your second question related to drug resistance, no, PEP appropriately taken will not increase your chance of drug resistance.

Good luck. Enjoy your upcoming holiday in the U.S. As for meeting me, well, that will probably be problematic, as I travel a great deal. But I certainly appreciate your kind comments and desire to meet.

Be well. Stay well. Safe travels!

Dr. Bob

$800 for a viral load test while I'm on pep? Jul 19, 2008

I took your advice and finally found an HIV specialist. Just like I asked you about my last exposure, he told me not to worry but insisted on me getting a vl test for early detection to see if I'm infected from my 4 month old exposure just because I had a big concern. That people who are poz and undetectable are still detectable and that this is a different kind of test to see if I am infected. He said that being on pep for a few days shouldn't interfere with the test.

Would you happen to know what he was talking about?

Have I been ripped off?

He said that If my symptoms were due to HIV, then this test will show it 100% at 4.5 months even though my antibody tests have been negative out to 18 weeks. CAN I BELIEVE HIM? I think it would be strange if I was already infected and on pep, so I took up on it.

negative antibody plus negative vl at 4 months? please! And this is just for my past exposure. Not my recent encounter. I'll handle that just fine.

I told him that you advised me to get someone to monitor me and I've already made 3 appointments and got the full 28 day treatment for free! Thank goodness for the w. village and your great advice Dr. Bob!

I'm going to start making donations once I get my job back. AND I'm not saying this so that you can answer yet another one of my 10 questions. Just please answer this one in particular so that I can discontinue my past fears. I just need to know what's going on or what to expect if my vl test comes back negative.

Also, if my vl test comes back reactive, should I get off the pep?

Response from Dr. Frascino


Sorry, but it's always difficult for me to try to interpret what was or wasn't said by another physician if I wasn't there to actually hear what he told you! If he is a certified HIV specialist, why not ask him what he's talking about?!?!? He should be able to explain what's going on in very understandable terms. If not, find another HIV specialist who can.

Regarding the other type of test he had you take, again I'm not exactly sure what it was. It could have been a quantitative test, such as an HIV plasma viral load (HIV PCR RNA) or a qualitative test, such as an HIV PCR DNA. Generally speaking, PCR tests are not recommended for routine HIV screening, but they can be helpful in certain situations. I would not trust an HIV PCR RNA quantitative RNA test performed for diagnostic purposes if the person was on antiretroviral therapy, because the antiretroviral drugs, if effective, could drive the viral load down, possibly to undetectable levels, thereby giving a false-negative result.

If your viral load comes back "reactive," the HIV specialist will perform appropriate confirmatory tests and, most likely, a genotype resistance test as well as a CD4 count. He would advise you to discontinue PEP if HIV seropositive. He would advise a HAART (highly active antiretroviral therapy) regimen if and when your CD4 count dipped into the mid-300 range, based on current treatment guidelines. Some of us are actually offering therapy at even higher CD4 counts.

My advice remains to work closely with a competent and compassionate HIV specialist with whom you can communicate freely. She will be your best resource to answer ongoing questions regarding PEP, HIV symptoms or HIV treatments.

Good luck!

Dr. Bob

elisa etst @ 14 weeks after PEP Sep 22, 2005

Dear Dr. Frascino,

I hope it is OK to address this to you directly? I have read your various responses on elisa test windows.The grey area seems to be with regards to the 13 week window if you take PEP.

I recently had a pontential sexual exposure to a HIV, in East Africa.( broken condom)Within 20 hours I was placed on PEP, a tripple regime, for a month. .8 days after potential exposure a blood sample was sent for a PCR test, which came back undectectable, (less then 400.)18 days after potential exposure an intracellular DNA PCR test was done, and the result was negative. I was assured that these should be sufficient to exclude HIV transmission to me.However I did also have a Elissa test as well as a rapid test 14 weeks after the date of potential transmission, which are negative. There is confusing advice on when to end the testing.May i ask why I read elsewhere that after PEP we should test for 6 months, and yet some sites suggests that count 6 weeks from end of PEP, ( I.E 10 weeks) You state as follows:THis is from PATHCARE south africa. "Most HIV ELISA tests become positive 3 weeks after exposure and all HIV ELISA tests should be positive 6 weeks after exposure." ( it's the "should" that has me worrying of course)

"In cases where the healthcare worker has taken prophylaxis, the time before tests are performed should be calculated from the day the prophylaxis was stopped."

Much research also suggests that all PCR / DNA PCR tests should only be conducted after PEP is concluded, as it can suppress viral load results, if they are present.The explanation I was offerred is that if there was an acute infection, and PEP was not effective, even this therapy could not completely suppress the intitial burst of viremia completely, and there vwould be some indication of viral load in the initial stages. Further more the negative Intracellular DNA PCR ( after 18 days) was proof of no virus was present in Plasma.

I am no virologist, but very ready to listen and learn, if you have the time to reply.

I hope that this is not an intrusion, however I am most apreciative of any explanations and advice that you can offer,as I have much faith in you.


Response from Dr. Frascino


Hmmm . . . . You're wondering if it's O.K. to call my Dr. Frascino??? Now there's a switch. Most folks worry about calling me Dr. Bob!

The specific answer to your question is rather complex and beyond the scope of this forum. However, you can read about it in the published guidelines "Antiretroviral Postexposure Prophylaxis After Sexual, Injection-Drug Use, or Other Nonoccupational Exposure to HIV in the United States." Recommendations from the U.S. Department of Health and Human Services Published in MMWR January 21, 2005 / 54(RR02);1-20 which can be downloaded at (

The bottom line is that PCR testing is not recommended during PEP, because antiretroviral drugs could suppress an HIV viral load to an undetectable level, thereby giving a false negative result. HIV-antibody testing (ELISA) for those who have had an HIV exposure significant enough to warrant PEP is recommended at baseline, 6 weeks, 3 months and 6 months after exposure. I agree with these recommendations/guidelines.

Hope that helps!

Dr. Bob

Failure to follow simple instructions! Oct 23, 2006

Hello once again Dr. Bob

Just to clarify clear instructions were given by you single antibody test at 3 months after the last exposure.

Failure to follow this simple advice was on my part for this I am sincerely sorry.

I have now had a test at 90 day / 13 week mark, I just received results over the phone - it was non reactive for HIV1, HIV 2 and P24. You are the only person I have told.

If you just could be kind enough to remove any further lingering doubts please answer the following: 1. You know my history well enough, I will not attempt to repeat it, is the last test I had definitive, can I stop this madness of testing, I must have given gallons of blood already. 2. Does the index value of the test matter, in my test the values have been: 6weeks 0.30, 8 weeks 0.31, 12 weeks 0.26, 13 weeks 0.30. None of them coming close to being above 1 which is reactive.

If you think the above questions are frivolous and unnecessary to answer, just a simple WOO HOO would do.

Regarding my anxiety, I am getting help and I have leveled with my wife from day one, as you say it may not be the best but it is the right thing to do.

I remain complicated only in name (thanks to you Dr. Bob).

Response from Dr. Frascino

Hello again Mr. (Un)Complicated,

1. Yes.

2. No.

WOO-HOOOO! See, absolutely nothing complicated about it at all!

Stay well.

Dr. Bob

Complicated Case Returns Oct 9, 2006

Hello Dr. Bob

I am afraid this will sound clichéd, but Dr. Bob I have visited your site often and I have to tell you in you I have witnessed the best of humanity, the absolute pinnacle you have opened my eyes to a lot of things and rid me of all my prejudices. Unfortunately, there have been timely reminders of the worst in humanity, in some of the hates mails you get. I am sure you dont worry about these assholes.

Well, its the return of Mr. Complicated. I certainly hope you remember me. A positive viral load test, which I think was a false positive (the lab and my Drs believe this), 6 weeks of PEP/ARV because of this result. I am sure you have the details in your record.

As you recall my 2 exposures of concern were medium risk, unprotected sex with women 3 months ago and the last at 11 weeks ago. You have rightly stated that all the viral load tests I had was invalid as I was on PEP. However, I think that Qualitative DNA Proviral test would still be valid, as these could detect even dormant viruses in the blood that are not replicating. I had two of this done, at 4 week and 6 week mark. I also had WB and ELISA (with P24) done at 6 week and 8 week mark.

My concerns are as follows is it likely that my first test of VL of 25,000 copies was a true positive. I have read that false positives usually have a low viral count, i.e.< 2,000. And the subsequent test were made undetectable due to PEP, (I had been on two weeks of PEP). But this would be illogical since the second test sample was taken just 3-4 days apart, and it came undetectable. Can the PEP or ARV be that effective? After receiving the positive result, I had it verified with a VL test at the second lab about 6 days after the first sample and that was also undetectable.

The Dr (who I now think was a quack), I was seeing at that time believed that this result of 25,000 copies was true (until proven false). And since VL was at a high setpoint, he thought I had virus for a long time. (This made me concern about all the encounters I had in the past, which were a few (one) I did not believe were risky at that time.) He could not offer a logical explanation as to why my baseline ELISA was negative. He later also changed his opinion about the initial test after subsequent tests were negative/ undetectable/ nonreactive.

What do you think could be possible explanations for a false positive result. I had a hepatitis shot at that time, also had genital herpes outbreak a few days after. The lab also thinks the samples could mixed up (as it receives 1,000s of sample from all over the country) and since it is in a different city to mine, my sample had to be flown to this lab thus more room for error. However, the pathologist thinks that mistake could have occurred in the handling. I think the third explanation biological disposition. But I would sincerely appreciate your opinion Dr. Bob.

Now for some good news I visited Singapore and got tested by Abbot rapid blood test (conducted by the great guys at AFA) and Oraquick oral test at a private clinic, both negative at the 10 and 11 week mark. I know this is not 3 months mark, but is this indicative of good news?

Do you still think that 3 months (12/13 week) test would be definitive for me, considering my 6 weeks of PEP and a (false) positive VL test. When do you think I can woo hoo and get on with my life, forgive myself for cheating on my wife.

Oh, yes I promise to donate, hope this will be in person, what a photo op that will be for me. But seriously, I think I would be in financial trouble if I am infected because I originally come from an underdeveloped country which does not have any national health schemes, they dont even have ARVs.

Love U Dr. Bob Mr. Complicated

Response from Dr. Frascino

Hello Mr. Complicated,

Welcome back to the forum. Once again I strongly disagree that your situation is at all complicated. Rather, your experience is simply the result of multiple errors in judgment. My assessment of your situation and advice remain unchanged from your original post (reprinted below). I see no real value in trying to identify or explain why a test that never should have been ordered produced a result you didn't expect. Viral load testing is not indicated for routine HIV screening. Period. Therefore interpretation of these test results becomes a moot point. What we can determine with great certainty is that your 25,000 copies VL test was a "false-positive".

Next, qualitative proviral DNA tests can be helpful in selected cases for identifying primary HIV infection prior to the development of detectable anti-HIV antibodies. However, once again, it is not recommended or FDA approved for routine HIV screening. That you've had two of these plus two additional ELISAs, p24s and WBs, all during the first eight weeks, is yet another error in judgment. To this you've now added rapid tests at the 10- and 11-week mark.

Clearly you did not heed the advice I gave in my initial response. As mentioned above, my assessment and my advice remain exactly the same:

1. A single HIV-antibody test at the three-month mark is all that you ever needed to confirm your HIV-negative status. (Tests taken prior to three months are not considered definitive. PCR tests are not recommended for routine screening.)

2. You need treatment for your anxiety, guilt and irrational fears of being HIV positive. To this I would add you should level with your wife. It's not only the best way to confront your guilt, but it's also the right thing to do.

3. Never vote Republican.

Thanks for your willingness to make a tax-deductible donation to The Robert James Frascino AIDS Foundation ( I am more convinced than ever that your "un"-complicated case will have a very happy and healthy ending. I look forward to your uncomplicated WOO-HOO!

Dr. Bob

Complicated case (amended)

Sep 8, 2006

Dear Dr. Bob

I am a hetero sexual male 33. I am also married but strayed a couple of times in the last 3 months. My last exposure was 7 weeks ago, me giving anal sex to a girl without protection, who said she had been tested and was negative, I am still in touch with her. I was inside her for about 5 mins or more before coming to my senses, withdrawing and washing. She also had her period during that time. I dont know whether any blood had got onto my penis from our encounter. Before this I had sex with a girl (student) when the condom broke, but I carried on unaware. This girl had also tested and was negative on ELISA/qualitative PCR after 12 weeks after our exposure. Anyway the GP I saw straight after my last exposure (48hrs) possibly misinterpreted my exposure risk and offered a basic PEP regime (duovir) and I went on it just to be on the safe side. My baseline ELISA was negative.

Another Dr. (a dermatologist) recommended a PCR RT Quantitative test, 2 weeks after which surprisingly came as positive with 25,000 copies. This is where my nightmare started. I had also given a second sample of blood (4 days after) to the same lab. After receiving the result still in a state of shock, I went to a different lab to have the same test done about 6 days after the first sample was given. Based on the first unconfirmed result, having a high viral count I was also put on ARVs by the same Dr. The lab that did the initial PCR, (I deduced later) found that the results of the first blood sample and the second sample were not matching and requested me to give a third sample 7 days after the first sample was given. Both of the two subsequent tests were not detectable i.e. negative. The lab, to make sure, also did a rapid immunocomb test and western blot test. It then said the first test was false, and admitted to their mistake but couldn't explain adequately where the mistake had occurred, most likely in the handling of the sample or interpretation. The PCR RT test at the second lab was also negative.

I was pretty distraught and saw an expert in the field of HIV. He recommended a DNA Proviral Qualitative test. I also got this done (3 weeks after the exposure) at the lab that had made the original mistake, this was also negative. I confirmed this with the pathologist there who had taken a personal interest in my case. This Dr was very encouraged but said that I should continue with the ARVs until 6 weeks post exposure, and stop after ELISA test is negative. This was because he did not want to lose the efficacy of the ARVs just in case I had the virus.

6 weeks after my exposure, my HIV 1,2 p24 test came negative. I also sent a sample for another PCR DNA qualitative test which also was negative, the lab again had run PCR RT, Immucomb rapid and western blot test as backups, as a favour to me, all negative.

I now have stopped ARVs, I still suffer from anxiety, also fear that with no ARVs or PEP, I am now seroconverting, suffering from mouth ulcers and sore throat. I don't have fever or rashes, but do get stiff neck and upper body muscle pains, I have these symptoms for 5 days.

My question is there a chance that I am now seroconverting because I am no longer on PEP or ARVs. Could they have interfered with my 6 weeks extensive test results and other negative tests after the first false positive. Did the lab really make a mistake, or were they right the first time. Logic dictates that they did make a mistake and they admitted it, because how can results be so different just within 4 days. I had been on 2 weeks of PEP at that time, maybe that interfered with the results of the second, third, 4th, 5th 6th PCRs both qualitative and quantitative. Also the Western blot, ELISA and Rapid Immunocomb. Sorry if I sound like the most tested person on the face of this earth.

My GP and the Pathologist, who is quite renowned in her field says I have nothing to worry about. Do you agree.

Your response will be greatly appreciated and thank you for all your good work.

Response from Dr. Frascino


There were several errors in judgment in this "complicated case" (which really shouldn't have been complicated at all!).

These errors in judgment include:

1. Your having unprotected sex.

2. The dermatologist recommending a PCR. First off, PCRs aren't recommended for routine screening, due to the possibility of false-positive tests. (I guess you learned this fact firsthand from your experience!) Second, ordering a viral load test while you were on antiretrovirals (PEP) to diagnose a potential HIV infection makes no sense whatsoever. (The antivirals could suppress HIV replication to undetectable levels, thereby giving a "false negative.")

3. Being placed on ARVs because of a spurious test result.

4. Continuing ARVs for six weeks when there was really no reason to do so.

My assessment of your situation is simple:

1. You had an HIV risk, unprotected sex, for which you should have gotten a single HIV-antibody test at the three-month mark to ascertain if you had contracted the virus.

2. Your initial PCR was a false-positive, once again demonstrating why I don't recommend them for routine screening.

3. I do not believe you are seroconverting, but I do believe you are suffering from anxiety, a condition for which I suggest you seek treatment. Because you remain so worried, I would suggest you get a single HIV-antibody test at the three-month mark. The odds remain astronomically in your favor that you did not contract HIV.

Your nightmare has several take-home lessons:

1. Unprotected sex isn't worth the risk.

2. HIV specialists should be consulted, if PEP is started, to assess the risk, optimize the therapy, manage complications and interpret follow-up tests.

3. PCR testing is not recommended for routine HIV screening.

4. Never vote Republican. (OK, I just threw that one in for good measure.)

Good luck. Fortunately for you, your complicated case will have a happy ending when all is said and done.

Dr. Bob

False Negative PCR Feb 13, 2007

I recently had protected vaginal sex and am concerned about my status. I experienced gingivitis like breathe and felt feverish shortly after the incident. I began viread and combivir 10 days after the incident and tested negative in an ultra sensitive PCR test 16 days after the incident. I experienced clear penile discharge 10 days after the incident that is not related to any other STD. My question is whether the PCR test may be a false negative because (1) the timeframe was too short or (2) the combivir and viread for 5 days before the test brought my viral loads too low for the test. Thanks

Response from Dr. Frascino


". . . Gingivitis like breath . . . ????" What the hell is that?

Several serious mistakes have been made in your case to date:

1. If you had "protected vaginal sex" and the latex condom was used properly and did not break, your HIV risk would be essentially nonexistent, even if you had garlic breath. Consequently, PEP (post-exposure prophylaxis) should never have been offered or taken.

2. If PEP was indicated and in your case it clearly was not it would need to be started as soon as possible and no later than 72 hours after the HIV exposure. Beginning Combivir and Viread 10 days after your non-exposure makes absolutely no sense whatsoever. The doctor who prescribed it demonstrated bad judgment and a lack of understanding concerning HIV transmission and post-exposure prophylaxis medications.

3. PCR viral load tests should not be done while you are on PEP, which is in essence comprised of potent antiretroviral drugs. Yes, antiretroviral therapy could drive plasma viral load (PCR) to undetectable levels.

My advice is simple:

a. Stop PEP. You had no real reason to start it and it was started way too late to be effective even if you did.

b. Get a single HIV-antibody test at the three-month mark to put your residual fears of being HIV infected permanently to rest. Testing prior to three months is not considered to be conclusive.

c. Send a copy of this post and my reply to the doctor who prescribed your PEP.

Dr. Bob

Mixed Status Couple
Got Tested and Thanks

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