Vulnerable to H.I.V., Resistant to Labels

NYTimes.com – By Marc Lacey

Mexico City – The 29-year-old is not gay. He wants that known. He did have sex with a man once, but that was the result of loneliness and his hormones’ being in overdrive, he said, not because of any attraction to men. He suspects that the one encounter was responsible for giving him the virus that causes AIDS. But he is not gay no matter what anybody may think.

Take the case of a 69-year-old married man, who did not want to be identified, and who is in a relationship with a younger lover, Carlos. Carlos, who has a girlfriend and a child and dresses as a woman, prefers the name Yessica.