Chris Crain flags a study that found the "introduction of effective drugs against HIV, the virus that causes AIDS, has not changed gay men's risk of contracting the virus during a single act of anal sex." The risks:

The riskiest type of sexual activity was receptive anal sex with ejaculation into the rectum; each such act carried a 1.43 percent risk of contracting HIV. If a man's partner withdrew before ejaculation, the risk dropped to 0.65 percent.

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