A study by the San Francisco Department of Health suggests that some AIDS patients taking antiretroviral medications are more likely to contract other sexually transmitted diseases than those not taking medication, possibly because they believe that the drugs offer blanket STD protection, the San Jose Mercury News reports. The study, published in The Lancet, found that cases of gonorrhea, syphilis, and chlamydia in San Francisco have all risen since AIDS drug cocktails became widely available in 1996. STD rates among those taking HAART nearly doubled from 60 new cases in 1995 to 113 in 1998. Susan Scheer, MD, who headed the study, said the data shows that HIV-positive people taking HAART for some reason, even though they have AIDS, are still going out and having unsafe sex. Researchers speculate that the effectiveness of HAART in controlling HIV infection may be falsely leading people to believe that the medicines also will shield them from contracting other STDs, making unprotected sex seem much less risky.