Expert: Terry B - 4/10/2007

Question
A few days ago I was in a public bathroom with a guy and we watched each other masturbate at the urinals, with a barrier in between us. We had no physical contact w/ one another. He ejaculated first, then me. I then went into a stall to wipe myself off and afterward, I noticed some semen on my pant leg, which was most likely my own semen. I wiped it off with toilet paper, but I started worrying that 'what if it wasn't mine and it dripped onto my pants from somewhere.' I know I had no cuts on my hands, but worried that maybe I had a hangnail that went unnoticed. I know HIV doesn't live well outside the body. Is there any chance of infection?  

Answer
Dear Mike:

Peace.  The short answer is that there is almost no chance of infection.  

The longer explanation is that even if the person was HIV infected (unlikely given prevalence of HIV in the population), and even if the semen on your pants leg was his (unlikely per your assumption it was yours, barrier in between you), your wiping it off with toilet paper suggests at worst a momentary exposure with potentially infectious fluids to probably intact skin; a low risk exposure in the first place.  

HIV 'lives' outside the body inside semen, vaginal secretions, blood and blood products, and breast milk; as long as these are in a fluid state the virus can remain intact within those fluids, and thereby infectious.  Care need be taken with these fluids (example, disposing of a condom) even outside the body, but in your example, the duration of exposure (brief), amount to which you are exposed (whatever might have seeped through the toilet paper), frequency of exposure (once), and route (natural barrier of apparently intact skin) argue to reduce your risk.  I would not even term this as a significant exposure.

Hope this helps, please avail yourself of local counseling and testing centers or health professionals to learn your status and reduce risk to yourself and others.

Sincerely,

Terry B