Oral sex vs Breast Milk exposure

Hi Dr. Hook:

I had a 15 second exposure just a week ago or so. Oral sex on a male with a couple rough pushes here and there and seriously for all of about 15 seconds total. Meaning he was not in my mouth the entire time. Anyway, I know he didn't ejaculate and not even sure if i was exposed to precum. So this exposure led me to ask a question in the community forum and I was told that Oral sex is not a risk for contracting HIV. As I was processing the answer and reviewing all the forums I was left with one question. Why does Oral sex not pose a threat but babies that are breast fed by HIV positive mothers have a very well established risk of contracting HIV? It doesn't make sense to me. They're both oral exposures.

So first, do you agree that my exposure was not a risk, do i have to test and can you explain the difference between the breast milk and oral sex exposure?

Thank you

[H. Hunter Handsfield, M.D.]

Oral sex indeed is low risk.  One estimate (from CDC) is one infection for every 10,000 exposures -- penile to oral, if the penile partner has HIV.  That's equivalent to giving a ** to infected men once a day for 27 years.  There are no data on whether brief exposures or more vigorous ones have lesser or greater risk, but in any case it's very low.

Exposure to breast milk is not equivalent risk to oral sex, and in any case the transmission rate from infected mothers to their babies by nursing is lower than you think.  By 6 months, around 10% of such babies become infected -- and remember that they are swallowing a few ounces of milk every day.  The low efficiency of breast milk transmission is due mostly to the small amount of infectious virus in milk.

From a risk assessment perspective, HIV testing isn't necessary after the sort of exposure you describe.  However, if you do not find this reply sufficiently reassuring, perhaps you should be tested for peace of mind.

In the future, avoid this sort of stress by asking your partners about HIV status before having sex with them -- even when relatively safe sex (like oral sex) is planned.

Regards--  HHH, MD