I am a male and I have read on all your transmission chart that
1) Receiving a blow job from a female is a negligible risk which means that in spite of body fluid exchange, there is no reported cases known known to have contracted HIV that way.
2) Rubbing penis to Anus without penetration ( touching anus from outside) is of negligible risk
3) Deep kissing is of negligible risk unless there is blood

My questions are

1) How much blood needed to guarantee HIV from one person blood stream to the other person's blood stream? ( You know there always tears in the mouth from the teeth or hard foods and sometimes there are some microscopic blood cells which can not be noticed) Do this microscopic cells enough to transmit HIV?!!

2) If someone has Herpes and on Valcycolovir 500 mg once daily for almost 9 months and have no sores or ulcers or inflammation and no outbreaks for almost a year, Would he be a high risk by receiving a blow job, deep kissing and anus rubbing to contract HIV from a woman?

NB: By the way I do not even think that I rubbed my penis to her anus. I just hugged her from the back with me and her naked so I assumed that my penis touch her anus, however, I believe if it does Me and she will feel that but we did not feel any penetration or any wetness. And when we did deep kissing we did not see or taste any blood.

3) I agree with you guys that HiV testing is recommended every 6 months but I want to know risk wise, if those risks are still negligible and do not require HiV testing or no?

Thank you


Thank you for your inquiry. From what we gather from the questions, you were asking about:

1) The amount of blood required to guarantee HIV transmission from one individual's bloodstream to another
2) The risk of HIV transmission from receiving oral sex, deep kissing, and possible anus rubbing, given that you have a history of herpes but have no active sores/ulcers
3) If HIV testing is required, given that the risk is negligible

To answer your questions:

1) The amount of blood required to guarantee HIV transmission from one individual's bloodstream to another differs from case to case, and is dependent on the HIV positive individual's viral load. An individual's viral load can be simply described as the amount of HIV virus present in the blood. The concentration of virus in one's body can change over time, and HIV treatment can reduce the viral load in the blood (and other bodily fluids) significantly. If an individual is HIV positive, receiving HIV treatment (medication known as antiretroviral therapy) can potentially make the viral load so low that testing cannot detect it. This is known as an undetectable viral load, and those with this status have effectively no risk of transmitting HIV (1).

2) From the information given, this scenario is determined to be at most Negligible Risk (there is no evidence or no documented cases of transmission. However, there is a theoretical possibility of transmission under certain extenuating circumstances). The scenario mentioned above does meet the 3 components of the transmission equation (see below). HIV transmission requires the transfer of an HIV positive fluid, coupled with a High, Low, or Negligible Risk activity that provides the HIV virus with direct access to the bloodstream.
Transmission Equation.jpg 
In your situation, the reason why there may be a negligible risk of HIV transmission is that you received oral sex from another individual, possibly without a barrier. As a result, in theory, if the individual performing the oral sex had an HIV positive fluid in her mouth, such as blood from a cut, that would provide an opportunity for the exchange of a potentially HIV positive bodily fluid to yourself through the urethra in the penis. If a barrier was used, then there would be no risk of HIV transmission.

Furthermore, kissing and non-penetrative anal touching in the scenario that you discussed would not carry a risk of HIV transmission, given that you have no active sores/ulcers. Sores and ulcers must be physically present/active at the time of the event to provide the virus with direct access to the bloodstream. 

Recommendation: there is no evidence or no documented cases of transmission. Refer to a healthcare professional for more personalized answers.

3) When we categorize a given event as Negligible Risk, this means that there is no evidence or no documented cases of transmission; however, there is a theoretical possibility of transmission under certain extenuating circumstances. In this scenario, we would advise for the individual to refer to a healthcare professional for more in-depth, personalized answers. Therefore, HIV testing may be required, depending on the event that led to the possibility of HIV transmission itself and the circumstances surrounding it. Nevertheless, if you believe that you engaged in an activity that carries the risk of HIV transmission, it is recommended to seek regular HIV testing to confirm your status.

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