I stand corrected, the AIDs virus cannot pass through the wall of a latex condom. I didn’t know that.
No worries!
For readers of The Straight Dope, Cecil Adams says in http://www.straightdope.com/columns/read/1178/can-hiv-pass-through-the-pores-in-latex-condoms:
“We could argue about these numbers, but let’s put this in perspective. Roland thinks condoms reduce AIDS risk by a factor of 3. A study cited by the government says they reduce it by a factor of 5. Avoiding high-risk sex partners, it’s believed, reduces it by a factor of 5,000.
In short, regardless of who’s right about latex, you’d be foolish to make condoms your only defense against infection. Abstinence or, more realistically, avoidance of high-risk sex partners are far more effective strategies.
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As for the substantive issue you raise, it’s true “the transmission of HIV by genital fluids most probably occurs through virus-infected cells since they can be present in larger numbers than free virus in the body fluids” (Jay Levy, “Pathogenesis of Human Immunodeficiency Virus Infection,” Microbiological Reviews, March 1993—an exhaustive treatment of the subject). But it would be wrong to construe this to mean that HIV is transmitted only by cells. When I spoke to Dr. Levy he readily conceded that HIV may be transmitted by free virus as well. He did add that the viscosity of semen may hinder the passage of such virus through the latex barrier.
We could debate the technical stuff all day. My point is this: for whatever reason—pores, improper use, etc.—real-world research shows condoms don’t offer 100 percent protection against AIDS. Maybe not, say the AIDS experts, but if you tell people that they’ll use it as an excuse not to use condoms. To which I reply: the arguably greater danger is that they’ll use condoms the way some weight watchers use Diet Coke—as an excuse to continue dangerous behavior (e.g., promiscuous sex, not gay sex per se). If that’s “anti-eros,” as some people seem to think, too bad. A friend of mine who died of AIDS attributed his illness to a wild weekend he’d once had. It’s hardly anti-sex to wish he’d stayed home. “
We do not know that the AIDS virus cannot pass through the wall of all latex condoms; in fact, with pores, fissures, tears and other manufacturing or user-induced nonconformance, they may.
With that said, in equivalent circumstances, condoms reduce the possibility of AIDS transmission, but human behaviour being what it is, the population of non condom users behaves differently than the population of condom users so therefore the protections claimed are not equivalent.