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HIV most infectious early on???

Apr 2, 2006

Well Doctor Bob, I wrote this message before and think i put it in the wrong catagory so i think this is the right one!

OK, ill start my question with explaining an article that i read from a website:, i was particularly focusing on the part of the article that said how HIV may be most infectious during the acute or onset of the transmission. They made a big deal about how the old risk% for one event of heterosexual unprotected sex that used to get me some sleep (.1) would jump to a much higher risk level if the person has RECENTLY contracted HIV. This now scares me for more than one reason...

this paragraph is the exerpt if you are interested The Risk of Infection per Contact The average risk of infection with HIV per sexual exposure is much smaller than that for other sexually transmitted diseases; however, because of the long period of infectiousness and numerous cofactors that enhance HIV transmission, the chance that an HIV-positive person who does not take precautions will eventually infect others can be quite high. The most extensive studies of the risk of HIV transmission per exposure have been conducted in industrial countries. Because of generally superior health levels and the ready availability of treatment for other STDs, the average risk of HIV infection per sexual contact in industrial countries is quite small (table 2.1). For example, the average chance that an infected male will sexually transmit HIV to an uninfected female partner by unprotected vaginal sex is estimated at between 1 and 2 per 1,000 exposures. The risk of transmission from an infected female to an uninfected male partner through unprotected vaginal sex is one-third to one-half as great (Haverkos and Battjes 1992).3 Thus, women are believed to have a somewhat greater probability of becoming infected from an infected male partner than the reverse. Anal sex carries the highest risk, especially for the receptive partner. The risk of transmission in unprotected anal intercourse, based on a study of men, is estimated to be between 5 and 30 per 1,000 exposures for the receptive partner. However, all of these figures very likely underestimateperhaps severelythe average transmission probability per sexual act. They are generally based on studies of transmission within discordant couplescouples in which one partner is HIV-positive and the other is HIV-negative. Couples that are discordant for a very brief period are not captured in these samples; thus, the most infectious individuals are likely to be excluded. These studies also fail to capture couples in which neither partner tests positive for HIV, but one recently has become infected. Below we review evidence that this may be the period of highest infectiousness. If true, then studies of discordant couples are measuring HIV transmission during a less infectious period (Mastro and de Vincenzi 1996).

I will explain my incedent. I had my first unprotected encounter with a friend i met thru my BEST friends. She seemed like a good candidate to see what it was like and then retire back to the old rubber. she was on the pill, graduated from the same high school as me (suburb of PA) and i thought i had reason to believe it was a low risk encounter. Well i found out thru 2 relatively short unprotected acts in one night, thru convo later, she told me nonchalant that she was a rehabilitated heroin addict. her ex bf got her on it and she kept relapsing but claims to always use her own tools. She has been single for some time and i know from friends she has had multiple unprotected sexual encounters, one being another guy in the rehab facility who did cocaine(near 2 weeks ago). She told me she got tested last in December and was negative and i believe all she is saying considered she is trying to clean up her act. She also got tested yesterday and is awaiting results of that. I am getting mine the 14th (6 weeks after. and follow ups)

My biggest concern is that if she tested negative in December,BUTTTTT she could have picked up the virus anywhere from before that and up to 2 weeks ago. According to the article, if she is in the acute stage could mean she could have been most infectious at the time i had unprotected sex with her and that no longer makes me feel very reliable about the .1-.2% risk i used to find confort in. I have been neurotic about this and have learned a valuable lesson i will take with me FOREVER. I have cried at the thought of having to face my parents with the bad news i could possibly face. I know i fucked up, just a stupid 21 year old who did the "a word" ASSUMED... I was always taught never to assume, but i did and if i get thru this, i will never take my beautiful life for granite for the way it was before.

Could you find any raw risk for a person in my position, remember that her status is unknown but did get tested negative december. I want to know please how much increased the risk of 1 act would have been theorizing that she was in the acute stage. I did two acts before i found out her past.

lastly, i want to thank you for being there for all these people, if i make it thru this clean which i know in my heart i will, I will not forget that when CDC gave me their half-assed responses, there was a man out there named Dr. Bob who actually cared about informing the world and not cause it was his job. You are doing more for the world than the majority of us that i see without this virus. If i could live my life the way you have one day, i would be a happy man with or without this virus. Thank you so much for being there for these people and myself when i had nobody to get answers from.

Response from Dr. Frascino


OK, enough with the "Dr. Bob superhero saving the world one anxious wreck at a time" stuff. I'll answer, I'll answer . . . .

Unfortunately there are no specific risk-estimate statistics I can give you, nor would they really matter anyway. The lesson here is a very simple one: if you have unprotected sex, you are placing yourself at risk for STDs, including HIV. Period. No matter how you hedge your bets or throw all caution to the wind, this basic fact remains the same. Also, because you've placed yourself at risk, you need to be HIV tested at the three-month mark. These basic tenants apply whether you've had sex with Mother Theresa, Madonna or a skanky crack whore working the Republican National Convention.

That said, I can also tell you that HIV infectiousness (ability to transmit the virus) is indeed greater when the viral load is highest. How much greater depends on many variables and cofactors viral strain, replicative capacity, plasma HIV RNA level, etc. There is no doubt that plasma HIV RNA levels (viral load) are indeed markedly elevated in primary infection (the period immediately after contracting the virus and before the body's immune system begins to kick in to fight the virus) and at end-stage disease (when the immune system is totally depleted and the virus has often become resistant to HIV medications). Viral loads can also increase transiently in other situations as well for instance with concurrent infections, vaccinations or the development of resistance to current HAART regimens. All of this brings us back to my initial point: unprotected sex equals HIV risk and HIV risk means you need to get tested. The rest is mere mental masturbation that can drive even a statistics geek positively mental.

So, do I think you're HIV positive? No, the odds are all in your favor that you did not contract the virus from your commando walk on the wild side; however, only your three-month HIV test will give you a definitive answer. One thing that I'm very confident of is that you've learned a very important lesson and that you'll never put yourself at risk again.

Thanks for your kind comments, and there is absolutely no reason why you or anyone else cannot live your life the way I live mine. In fact, I invite you to do so. It's a wonderful way to live.

I'll send you my very best good-luck/good-health karma that your three-month test is negative.

Good luck.

Dr. Bob

Thanks Dr. Bob...please answer ....still worried

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