Multiple HIV Tests; Which, if any, are conclusive?

On April 11th, I had a one night stand. On the April 15th, I took an HIV antibody test along with a HIV RNA PCR test. My results came back negative. On May 12th, I took both tests again, and both came back negative again. My question is, should I consider these results conclusive? Or should I get tested one more time being that is past three months now? Also what kind of HIV test do pregnant woman get?

We’ll start with the simple question first. Most women get a standard ELISA antibody test for HIV. This is because this test is relatively inexpensive, and is processed at a laboratory, meaning that it will give the most reliable test results.

At four days after the exposure, there is a possibility that the RNA test would detect the viral presence, although the chances are slim. The HIV antibody test would not be reliable at all after such a short amount of time.

At one month after the exposure, the HIV RNA PCR would be extremely reliable. Unfortunately, I cannot consider this test conclusive, because there is no published material stating that this would be conclusive after one month. On the other hand, there is absolutely no reason why an RNA PCR would not detect the vast amount of virus present one month after infection.

Given the rapidly replicating nature of the HIV virus, you should have virus present, especially after one month, and there should be more than enough to be detectable on the RNA PCR test. The antibody test, while not conclusive, will give you a mere indication after one month, with about 50% of the population having a detectable amount of antibodies. You need more of the virus in your system to show a positive result on the HIV antibody test than you would need to show a positive result on the PCR test. This is because the virus must be present in your system long before any antibodies are produced, all the while, the virus has been replicating at an alarming rate. Thus, the HIV RNA PCR results would have been extremely reliable during your second round of testing.

If you have an ultrasound 3 months after intercourse, and there is no fetus developing in the womb, then there is no point in waiting for a baby to kick after 8 months. Similarly, once you have determined that there is no virus in your system, there is no reason to think about redoing an antibody test at 3 months, because antibodies are only produced if there is virus. The PCR test looks directly for the genetic material of the virus itself. Anybody can say that a PCR test could miss the presence of HIV in the blood one month after exposure, but it is also possible, and I contend, more likely, that you could get hit by a truck on the way to get a test that you didn’t really need in the first place (a 3 month antibody test), based on the results of the PCR.

On the other hand, the results aren’t conclusive from any research standpoint. This means that in order to get conclusive results, you would either need to do a DNA PCR after one month, which the manufacturer considers conclusive after one month, or an ELISA antibody test after three months.

Remember, the best approach is to practice safe sex, by using protection, and prudence in choosing partners. If you choose not to use protection, it is imminent that you and your partner have been tested and are known to be previously uninfected.