The vastly disproportionate rates of HIV among African-American men who have sex with men (MSM)—an estimated one in five new U.S. infections occur among this group—are linked to unemployment, lower socioeconomic status and the presence of other sexually transmitted infections (STIs).

In a six-city HIV Prevention Trials Network study of 1,500 black MSM, researchers found that, when compared with HIV-negative black MSM, those recently diagnosed with HIV were more likely to be unemployed, to have had receptive anal intercourse without a condom, and to have syphilis, rectal gonorrhea or chlamydia.

“None of these things are just in isolation,” says Kenneth H. Mayer, MD, medical research director and co-chair of The Fenway Institute of Fenway Health and the study’s lead author. “You have to think about a bunch of different responses if you want to get a handle on decreasing the serious epidemic among black men who have sex with men.”

Part of the problem, Mayer says, is that economic challenges may lead black MSM to remain fixed in certain communities, where there is already a high HIV prevalence, thus raising their chances of exposure to the virus.