Friday, March 19, 2004

When The Luck Runs Out

Those of us who do HIV prevention don't like to talk about long-term exposed seronegatives. (You can tell, because we've given them a complicated, unobvious name.) These are people who continue to test HIV-negative after many years of unprotected sex with an HIV-positive partner. The reason we don't like to talk about them is because we're afraid that every high-risk person out there is going to be convinced that they'll be in the bulletproof group too.

Researchers at the University of Washington have been studying these folks, and have found that they do have very small amounts of HIV in their systems. They never test positive because their immune system never produces antibodies to HIV - but somehow, they've managed to prevent the virus from replicating inside their T-cells. So their T-cells aren't destroyed by HIV, and they don't get sick. We don't understand how that happens, although obviously, we'd like to be able to bottle whatever it is and distribute it to everyone.

At the most recent Conference on Retroviruses and Opportunistic Infections, the UW team reported that 12 men in their group of 94 long-term exposed seronegatives had finally tested HIV-positive. Here's the kicker: none of them were infected by their long-term partners. The partners' HIV was too genetically different from the newly-infected guys' HIV for them to have been the sources of infection.

I learned about this study at a dinner presentation last night. When the speaker got to the genetic comparison, a ripple of laughter swept through the room. It's really not funny, but I'll admit that there is a certain dark irony to it. These guys thought they were immune to HIV, so they could cheat on their boyfriends without consequences. Turns out, they were only immune to their own boyfriend's HIV. And their participation in the study turned up unexpected proof that they'd been sleeping around. Poor bastards.