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Negative ELISA and reactive P24

Mar 8, 2008

I dropped you an e-mail earlier in the week and I thank you very much for answering the e-mail.

Also, please be advised that I wish to make a donation to your foundation via credit card. Please let me know how to do this.

In follow up to your answer to my question, I would like for you to address the following:

As you may recall, I had the negative elisa on the 11th day as well as the 57th day. A negative RNA on the 11th day and then the Western Blot on the 57 day and the p24 band came back as reactive. No other bands came back reactive.

In reading various articles on the internet, it appears that the p24 band is one of the primary ones to indicate HIV as well as the primary one that may come back reactive but indeed a person may be negative for HIV. Please talk a lot about this as well as offer some insight to all of the bands and what they mean.

Also, what are retroviruses and could you name 5 or 6 of the more common ones.

I have since learned that the guy that I had sex with that was positive was raped at 15 and that is how he got HIV. He has been on medcations since that date and his viral load is under 50. I understand that this is undectable. On the other hand, I understand that when a viral load test is taken it only measured what is in the blood- only about 2 percent. Is that correct?

With that said, what do you feel my chances were of getting infected from him since his viral load was under 50. I read somewhere that lots ofthe HIV virus is trapped in the prostate glad as well as the membrane of the rectum and thus while the viral load may be undectable in the blood, it could be high in the two areas mentioned. Please offer insight and thoughts into this subject.

Finally, please talk a little about the DNA-PCR test. Various sites say that it is 95% accurate at 28 days. However, other sites say that it is not good to get at that point as there are too many false positive readings. Please offer your inight on the DNA-PCR to detect HIV and at what point it should be used - (number of days) as well as its accuracy. When would you recommend a person get the DNA-PCR test?

Are there any other good tests for early detection of the HIV virus.

In closing thatnk you very much for taking time to answer the iniial question as well as this question. You are very kind to take time from your schedule to help others. You are certainly a hero in my mind. Keep up the good work.

And yes, I am still a nervous wreck. I look forward to hearing from you.

Response from Dr. Frascino


So your request is:

1. I talk a lot about p24 bands and offer insight into all bands and what they mean;

2. I discuss retroviruses and name five or six of the more common ones;

3. I discuss technical aspects of viral load testing;

4. I discuss your chances of acquiring HIV if your partner's viral load is under 50;

5. I offer insight and thoughts about anatomical HIV viral reservoirs;

6. I discuss DNA-PCR test accuracy and recommendations for use; and

7. I discuss tests for early HIV detection.

Did I leave anything out? Dude, don't you think you are being just a wee bit unreasonable? If I responded in detail to your seven questions, I would be typing for the next five hours. And I can tell you right now that's not going to happen. Besides, nothing I say is going to change the facts of your potential exposure or the ultimate results of your HIV tests. If you want to learn more HIV, HIV tests and HIV transmission, the information is all readily available on this site, in its archives and at the related links. This includes answers to your 7 questions! I see no purpose in my reiterating this information merely because you are "still a nervous wreck." Instead I'm going to repost your original question and my original response. It clearly outlines your problem (a physician who ordered inappropriate tests) and what you need to do next (get tested at the appropriate time using the appropriate tests). The rest is just mental masturbation.

The only additional comment that I'll make, based on the new information you provided, is that if indeed your partner's HIV plasma viral load was undetectable, the chances of HIV transmission would be very dramatically decreased. This fact, plus the test results you've had to date, would put the statistical odds that you did not contract HIV astronomically in your favor.

Regarding donations to the Robert James Frascino AIDS Foundation, donation information can be found on the foundation's Web site at Please note donations to my foundation should be made out of generosity, compassion and the desire to help those in desperate need. They should not be made or offered in an attempt to get me to respond to questions. My advice in this forum is free and available to all. I am sending you my good-luck karma that your definitive HIV test will be negative, as I very strongly believe will indeed by the case, OK?

Good luck.

Dr. Bob

Negative Elisa and reactive p24 Mar 3, 2008

I am a nervous wreck.I am a 26 year old male. On December 30, 2007, I have unprotected sex with a person who I now understand is HIV positive. We both engaged in anal sex and he ejaculated in me and I ejaculated in him. We also rimmed each each and engaged in oral sex. He states now that he is 33 and has been HIV postive since he was 15. He states that he is on medication and that his viral load is undetectable. (I have read that viral load tests the HIV load in the blood and not necessary the HIV load in the prostate gland or some gland or membrane in the rectum. With that said is it true that the HIV virus could be present in these two areas even if the HIV viral load in the blood is undetectable.) On the 11th day after we engaged in the unprotected sex my doctor did an RNA tests as well as an ELISA and Western Blot test. He advised that all cam back negative. How accurate is the RNA blood tests on the 11th day after an exposure? Now eight weeks later to the day, he does another ELISA tests and it comes back negative, however, the Western Blot test comes back with the P24 as showing reactive. While my physician has stated that the test is indeterminate like I said earlier, I am a nervous wreck. It did not help that whenI asked the physician his gut feeling, he did say that he could understand why I was concerned and if it was him he would surly have a lump in the back of his throat. I am going back tomorrow at the nine week mark exactly to have a retest done. With all of that said, I have several questions. In your opinion, has enough time passed based on the type of tests done to determine if I am HIV positive? It is my understanding that the first band to appear is the 24 band. How concerned should I be that this band has appeared at the 8 week mark and does it probably mean that the other bands will soon follow as I may just be beginning to servoconvert? What other tests could I ask my doctor to perform so that I could get some immediate results -- good or bad at this point, the nine week mark? In clsoing, whta is your opinin? Do you think I am HIV positive or that in the weeks ahead the ELISA test and the WEstern Blot tests will change from negative on the ELISA to positive and from inderminate on the Western Blot test to postive. Thanks very much for your thoughts and I look forward to a response.

Response from Dr. Frascino

Hello Nervous Wreck,

Agreed: Unprotected sex does place you at some degree of risk for STDs, including HIV. And testing is warranted.

However, your current physician is certainly not doing you any favors and please feel free to let him know I said so. He is ordering improper tests at improper times and not interpreting the results correctly!

First a few facts:

1. The proper test for HIV screening is an HIV-antibody test (ELISA, rapid test or equivalent). If this initial screening test is repeatedly reactive (positive), then and only then should a confirmatory Western Blot test be ordered.

2. HIV-antibody tests taken prior to the three-month mark are not considered to be definitive or conclusive.

3. HIV RNA PCR tests are not recommended for routine HIV screening, due to the rate of false-positive results, other technical considerations and cost.

That said, you've had a number of tests run inappropriately. Your two ELISA tests (11 days and 8 weeks) are both negative. This is encouraging, but not definitive. The Western Blot with a single p24 band is not interpretable, because it means nothing without a preceding positive ELISA. The negative RNA PCR is an inappropriate test, but nonetheless is negative.

I see no reason for a lump in the throat or concern based on your laboratory tests to date. What is of concern is your current doctor's competence (or lack thereof) in appropriately screening for HIV disease!

Here's what you need:

1. An ELISA (or rapid test) at the three-month mark. If negative, get a follow-up ELISA (or rapid test) at six months. If that remains negative, you have definitively dodged the HIV bullet.

2. If your three- or six-month ELISA or rapid test is reactive (positive), get a follow-up confirmatory Western Blot.

3. A more competent physician!

Good luck!

Dr. Bob

Trying to move on
Once-off Exposure

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