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Dec 15, 2007

Hello Again Dr BoB.

It is me again if you recall i was guy back Nov 18 had vaginal intercourse with a sex worker and got blood on my penis from her pms cycle and wiped it off with a sock before you had a chance to respond to my question i went to a infections disease practice and they put me on truvada for 30 days for pep and me being i know you don't recommend pcr testing and you only recommend elisa at the 3 month point for a accurate result sorry i had a pcr test done at the 18 day point which was negitive how accurate would this be would the truvada cause a cause a false negitive my brother was a big fan of yours he passed away on thanksgiving day in 2004 from comlications of aids it is great what you do for this cause. Here in the deep south people,hospitals,clinis still have no clue about hiv or aids the hospitals in Mobile Alabama acted like they had no clue what pep was i had to be very persistant i finally found the infectious disease practice in Pensacola Florida and it sounds like my case was not worthy for pep i think the only reason they put me on is when i was a child i had an accident and was bed ridden and where a cath in penis wich made the opening larger than normal and my persistance i will be making another donation right now I will start wearing my socks on my feet.

Response from Dr. Frascino

Hi Big Easy Messy Squeezy Guy,

First I should clear up a technical point. The blood was from your sex worker's menstrual cycle not her "pms cycle". PMS stands for pre-menstrual syndrome( Q: What is the difference between a woman with PMS and a snarling Doberman Pincher? A: Lipstick!)

This question actually comes up fairly frequently. While HIV RNA PCR can be useful in selected situations for helping to identify acute infections prior to the development of detectable levels of anti-HIV antibodies, the test is not recommended for routine HIV screening, due to the rate of false-positives; other technical considerations, such as the fact that the sensitivity of the test depends on the viral load; and finally cost. In particular, trying to use HIV RNA PCR for diagnostic purposes while on antiretroviral therapy makes no sense, as the chance of a false-negative result would be very high. (See post from the archives below that explains why.I'll also post your original question.)

So what should you do now? Even though I wouldn't have recommended nPEP (nonoccupational post-exposure prophylaxis), now that you are on it, you should follow the published guidelines for post-nPEP testing. You can download a copy of these guidelines at Thanks for your donations to The Robert James Frascino AIDS Foundation ( They are warmly appreciated. My good-luck/good-health karma has been sent along with my good wishes for happy, healthy holidays.

Dr. Bob

RNA testing after anal sex Dec 9, 2007

After condom break during receptive anal sex 7 days ago with a partner of unknown hiv status, I am wondering how to proceed with testing. I am on PEP, started within 7 hours. Should I proceed with RNA testing at 12 days? I will certainly do the 6/18/36 week antibody testing. Should any of these times be altered because of PEP? Also, should I repeat RNA at 28 days? I have heard that such testing is fairly definitive. Is this true even with PEP?

Also, what about PEP? How many people actually seroconvert when taking PEP? I have not seen the statistics on this.

I am more worried about accuracy and getting quick answers than cost, and I am willing to risk the false positive to possibly get peace of mind.

Response from Dr. Frascino


HIV PCR RNA testing is not recommended for routine HIV screening. Period. It is particularly not recommended while on PEP! Think about it. PEP involves taking antiretroviral drugs. If you were HIV infected, taking antiretroviral drugs could drive HIV viral load (RNA) to undetectable levels. If you then try to use HIV PCR RNA as a screening diagnostic test you will get a false-negative result. As I have said numerous times before, HIV PCR RNA plasma viral load testing should not be used for routine HIV screening!

My advice is that you follow the published guidelines for post-PEP HIV testing. You can download a copy at

Finally, regarding efficacy of PEP and the number of people who seroconvert despite PEP, there are no statistics, as there are far too many confounding variables to consider, such as differences in PEP regimens, viral strains, interval of time between exposure and start of PEP, etc. Also, since we know PEP is at least partially effective, it would be unethical to do placebo-controlled clinical trials. What I can tell you is that PEP is not 100% effective. There are PEP failures despite starting immediately after an exposure and taking the medications as directed. (Yours truly is a prime example!) At this point you are doing everything you can. The odds remain very much in your favor. My only advice is to take your medications as directed and follow the recommended guidelines for post-PEP testing.

Good luck!

Dr. Bob


Hello Dr. Bob.

Last night i had sex with a sex worker we used a condum but we were finished with vaginal sex she in formed me she had just started her period she had blood everwhere after she pulled the condum off with out me not knowing i wiped it off with a sock the blood was there and smeared it all down my penis what are my risks should i go try to go get pep.

Thank you for the work you do i will be a 100.00 donation to foundation right now.

Response from Dr. Frascino


PEP is recommended for significant HIV exposures. Based on the information you provided, I would not recommend PEP. A rapid test at the three-month mark is all that's required. The odds are astronomically in your favor that you did not get infected from this messy squeezy in the Big Easy, OK?

Thank you for your tax-deductible donation to The Robert James Frascino AIDS Foundation ( It's both warmly appreciated and urgently needed. In return I'm sending you my good-luck karma that your definitive three-month test is negative.

Be well. Stay well.

Dr. Bob

Dr. Bob, will you give me a job?

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