When Robert Sheriff learned he was positive in 1996, he and his neggie wife, Wilma, dragged a third party into their bedroom: a condom. “[Wearing it] was like trying to make love through a brick wall,” says Sheriff, 44. Six months after he started HIV meds—his viral load having dipped to 13,000—the couple dumped the latex. “We weren’t connecting like we used to,” Sheriff explains. “We’d already gone five years without [condoms] before my diagnosis, and she never tested positive.” Indeed, Wilma, 46, remains negative today. So the Sheriffs weren’t surprised to hear that a Spanish study of straight serodiscordant couples in September’s Journal of AIDS showed that the rate of HIV transmission among participants had fallen 80% since the 1996 debut of HAART cocktails.

The project recruited 393 mixed-status,heterosexual partners from 1991 to 2003. The couples were categorized by their recruitment time (pre-, early- and late-HAART) and followed until 2003. HIV prevalence fell from 10.3% pre-HAART to 1.9% in late HAART, whether or not the couples had had unprotected sex. Indeed, not a single negative partner of an HIVer on meds was infected. Although the study examined only heterosexuals, lead author Jesus Castilla says the reduced transmission is “applicable to homosexual [populations]” (unprotected anal sex, however, is still considered riskier than vaginal sex).

Castilla warns that this study shouldn’t encourage mixed-status couples to reject condoms. The likelihood of transmission can rise with any number of sexual risk factors, including rough sex and poor med adherence. Robert Remien, a scientist at Columbia University’s HIV Center for Clinical and Behavioral Studies,emphasizes that “transmission is always possible, regardless of viral load” and the presence of HAART. What’s more, condoms protect against other sexually transmitted diseases, which spike HIV risk and endanger immune systems. But the Sheriffs aren’t budging:  “I’m not advocating unprotected sex,” Robert explains. “Wilma and I spent six months apart thinking about the ramifications of this disease in our lives. This is the decision we came to mutually, and it’s the right one for us.”