Expert: Terry B - 12/21/2007

Question
Acting totally out of character I had unplanned sex with a female friend a
month or so ago. There was no penetration but there was a lot of fingering.
Prior to this I have never had sex before, but my friend is sexually active and
has admitted to having unprotected sex with her partners (both male and
female) before me. She has never been tested but is a regular blood donor,
and to date her blood has never been rejected. Her previous sexual
relationship prior to being with me was in 2006, and she donated blood after
that relationship ended.

What is the risk of transmission, assuming she is HIV+?

Answer
Dear Panicked:

Peace. Contact with vaginal secretions on intact skin (heavy petting or "fingering") would not constitute a significant exposure even with a person who is known to be HIV positive.  I see no significant risk of HIV transmission in what you describe.

Now to the most difficult part of your question - using blood donation as a screening tool for HIV infection.  We know that there is a period of time between initial infection with HIV when a person may have very high viral load but has not produced sufficient antibody for a positive test result.  Even with more sensitive tests used by the blood banks, there is some statistical risk.  

Please ask your friend to avail herself of a STI/STD/HIV testing clinic BEFORE donating blood. While the screening tests used by the blood banks are highly accurate, they are not perfect.  However rare, a false negative would mean infection of whomever received the donated blood.
(See http://www.avert.org/hivtesting.htm#q3a for more information on testing.)

The best to you and yours.

Terry