The following post originally appears on The Washington Post under the title, “The black HIV epidemic: A public health mystery from Atlanta’s gay community.” 

By: Jeff Guo

ATLANTA — In the early 2000s, a young researcher at the Centers for Disease Control named Greg Millett set out to solve an epidemiological mystery. Nobody could explain why black Americans, particularly black gay men, had such high rates of HIV infection compared to the rest of the population. How were they putting themselves in so much danger? What were they doing differently from everyone else?

Millett began with a survey of the published research, but that only seemed to raise more questions. Study after study seemed to arrive at the same conclusion: Black gay men take fewer risks in the bedroom than white gay men. They are just as, if not more, consistent about condom use and STD testing. They have fewer sex partners. They are less likely to abuse injection drugs. Despite all this, black men—gay, straight, or bisexual—are 6 times more likely than white men to contract HIV in a given year.

In 2006, Millett wrote up these findings in the American Journal of Public Health, alongside a careful review of alternate theories for what was going on. Some thought that genetic risk factors or circumcision or the prison systems played a role, but Millett found that the most promising theories involved healthcare disparities. For instance, black men are more likely to have other STDs like gonorrhea or syphilis, which increases one’s risk of contracting HIV. The sheer prevalence of HIV in the community means that despite getting tested just as frequently, black men are still more likely to have an undiagnosed infection, a circumstance that makes them more likely to pass on the disease. Lack of healthcare access raises another issue, in that those who do have HIV are less likely to be on the antiretroviral therapies that could make them less infectious to others.

But those explanations didn’t seem enough to account for the vast chasm between black and white HIV rates. So Millett began to consider another theory, a stunningly simple one, that could tie all the facts together.

Millett, who is himself black and gay, was well aware that black men tend to have sex with other black men, almost exclusively. What if that behavior was putting them in danger? It’s simple mathematics: the closer-knit a community is, the more any risk factors for infection become amplified. He began to wonder: What if the most dangerous thing a gay black man could do was what came naturally to him: to date the people he was attracted to, the people he was friends with, the people who surround him?

Greg Millett grew up in Brooklyn, the son of a United Nations staffer and a microbiologist. As a child he dreamed of becoming a civil rights lawyer, of putting the ghosts of racism and inequality on trial. To steel himself for those future battles, he landed a spot at conservative Dartmouth, which in the late ’80s was rending itself apart over sexism and race. These were the fires that would forge his identity, Millett thought, where he would learn to assert himself as a proud young gay black man.

Then his friends back home started getting sick.

As the AIDS crisis reached its crescendo in the late ’80s, Millett began to realize that the injustice was right here, in his calendar filling up with funerals and in the indifference of the federal government. By the age of 25, he had watched 20 of his friends and acquaintances die of AIDS. So Millett set aside his law school plans and began to volunteer at the Gay Men’s Health Crisis, a non-profit dedicated to fighting AIDS. He organized clinics to teach men of color about the risks of HIV and how they could have safer sex.

Even back then, he says, it was clear to him that black communities were disproportionately affected by the virus. He couldn’t prove it yet, but he went to graduate school to learn about how he could help. In the late ’90s he joined the CDC to organize studies of gay and bisexual men. By then, new drug cocktails were holding the disease at bay. The number of people who died of AIDS fell for the first time in 1996. TIME named HIV researcher David Ho its Person of the Year, calling him “the man who could beat AIDS.”

But the crisis had not abated. In 2001, a landmark study from the CDC found alarmingly high numbers of young gay men testing positive for HIV. Infection rates were particularly bad for black gay men: Nearly one third of black gay men between 23-29 were found to be HIV-positive.

Inside the CDC, an order came from high up: Find out what was going on with black gay men. At the time, Millett recalls, there were few black scientists in the department, and certainly nobody who was black and gay and out. Millett was assigned to untangle the different theories about why this community—his community—was getting hit hardest by HIV.

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