Expert: Terry B - 5/18/2007

Question
Hi. I wanted to know, if a person has AIDS or is HIV positive and has unprotected sex with their partner, are they pretty much guaranteed to pass the virus on to their partner? In other words, are there cases where couples exist (where one person is infected and the other is not) and they have unprotected vaginal sex with their partner, and the partner remains free of the virus? Or does living with the virus mean you could never have unprotected sex with your partner, and doing so pretty much guarantees that you will infect your partner?

Answer
Dear Steve:

Peace.  Interesting question.  There are a small group of people who are (by genetics) missing receptor sites on their blood cells, and apparently are therefore much less likely to contract HIV.  Also, not every exposure leads to infection; many people have been exposed to HIV infected blood, semen, vaginal secretions.. and not been infected.  The risk exists along a continuum, with the amount of fluid, concentration of virus in the fluids (highest at initial infection and late HIV disease), amount of area across which the fluids are distributed, duration of the exposure, frequency, immune status prior to infection, and general health (presence of other illnesses or infections).

Couples who are made up of one person infected and one not infected are referred to in research as "Serodiscordant" and there is some data on rates of transmission available through www.unaids.org and other sites, also information on how to reduce risk and retain intimacy at www.thebody.com and other sites as well.

I hope this gives you the information you need to answer your questions.

Sincerely,

Terry