“Bug chasing guys get my attraction,” writes a Twitter user with the handle Arab Poz Guy, “because they crave what I have.” What he has is HIV.

The 36-year-old, to whom Vocativ spoke on the condition of anonymity, is HIV-positive and an active member of a small subset of men known as bug chasers. These aren’t men who have unprotected sex with other men simply because they enjoy it, or because they’re in committed relationships. They’re men who deliberately seek out sex partners who want to get infected — or infect others — with HIV.

The bug chasing phenomenon has existed since the early days of the HIV crisis. Though much about the epidemic has changed since the virus first surfaced in 1981 in Los Angeles, bug chasing itself has persisted — and perhaps even flourished — in recent years online, having found new purchase on social media platforms like Twitter and Tumblr. Because these platforms’ terms of service are relatively lax regarding sexual content (both allow varying degrees of nudity and pornography), they’ve become an online haven for chasers. A search for hashtags like #bugchaser and #neg4poz on Twitter uncovers an active community, and users — some with thousands of followers — post regularly. It’s a similarly popular topic on Tumblr, where Vocativ found dozens of users sharing explicit videos and pictures depicting and encouraging unprotected anal sex between men, in posts fetishizing HIV transmission.

Vocativ reached out more than a dozen of those individuals across these networks. One of them, Arab Poz Guy, is what the community calls a gift giver: He knowingly infects other men with HIV, with their consent. When he spoke with us, he said he’s been at it for more than decade, having unprotected sex with bug chasers. “I always have unprotected sex, but the desire to poz the guy is stronger when the guy wants it,” he says, using “poz” as shorthand for “positive,” as in making someone HIV positive.

The sexual excitement of bug chasing — the element of real risk and an uncertain outcome that accompanies an unprotected sexual encounter — was a primary motivator for the men with whom Vocativ spoke. “I enjoy it for the thrill of not knowing if this will be the time that I am infected,” one man told us.

Another user referred to a belief that HIV is a distinct part of gay identity, and so getting the virus becomes seen as a means of “bonding” with that community. Still others framed it as an issue of freedom. One man called it “empowering,” suggesting that contracting HIV allowed him to live worry free, as contracting the virus eliminates the “what if” factor in his sex life. A Tumblr user, who claimed the large size of his penis meant he couldn’t wear condoms, echoed that belief: “I knew I couldn’t use condoms. I figured it wasn’t worth worrying about so I asked [my friend] if he’d cum in me over and over again until I got it so I wouldn’t need to worry anymore.”

Arab Poz Guy said Twitter and Tumblr have become a new home for the bug chasing community, but he noted that it’s been an online subculture for years, moving from one dot com to another as sites shut down and better ones came along. “Ten years ago, [this] social network was not strong as it is now. The biggest hangout was through certain sites, like BNSkins, which got closed. Then there was a camming program,” he writes, referring to a webcam site called ICUII. “It is still available, but it is not as it used to be. Twitter and other social media like Facebook [and] Tumblr made things easier.”

One gift giver, a 55-year-old who uses the pseudonym Larry Hewes and is active on Twitter and Tumblr, agreed the new platforms are filling a vacuum left by older websites that have been taken offline. “The biggest [online bug chasing community] was a site called Poz Convert, because its only point was to let chasers and [gift givers] find one another. It began having technical issues, and was down often in March, and went offline permanently April 1.” Now bug chasers contact him via Twitter and Tumblr. “I get slightly more new contacts through Twitter than Tumblr,” he explained, “although the ones through Tumblr are increasing.”

Hewes, who says he discovered he was HIV positive in January and cannot afford to take antiretroviral medication, says he started blogging on Tumblr after his diagnosis. He posts often, sometimes multiple times a day, sharing pornography and answering questions from bug chasers. He also helps arrange hookups with gift givers and advises bug chasers on how they can increase their chances of becoming positive during a bareback sex session (one tip: induce bleeding). Hewes also makes and receives direct offers of solicitation to and from bug chasers looking to become infected.

The phenomenon of bug chasing — and media coverage of it — long predates the internet. One of the first articles to mention bug chasing outside of LGBT media appeared in a September 1997 issue of Newsweek. The AIDS epidemic, while by no means over, was finally slowing: AIDS-related deaths dropped from more than 50,000 in 1995 to fewer than 19,000 in 1998, according to figures reported by the CDC. Entitled “A Deadly Dance,” the article pointed out that AIDS-related deaths had fallen by 23 percent from a year earlier, thanks to antiretroviral drugs and other prevention efforts.

The story, by Marc Peyser, stated “a tiny but visible group of HIV-negative men are actually looking to get infected.” The article claimed some gay men “have sought to transform HIV from a death knell to an empowerment tool,” and quoted one activist who said: “If you’re HIV positive … there is a sense of community.” A documentary released in 2003, called “The Gift,” also reported that at least some bug chasers wanted HIV due to the “sense of belonging” they believed it would give them.

The idea of HIV as a sort of access key to a distinctly gay community — a sentiment brought up in the documentary and echoed by men we talked to online — is a common one in seeking to explain the seemingly inscrutable motivations of this community. Another is the risk itself.

“For some in this small group, there is something enticing about engaging in taboo sex or sex [that] we are told is unhealthy for us,” Kalyani Sanchez, director of HIV prevention and health education at Gay Men’s Health Crisis in New York, told Vocativ.

Joe Kort Ph.D, a certified sex therapist, offered a different view, suggesting that a self-destructive behavior like bug chasing may be a result of childhood trauma. He told Vocativ that, especially in a certain era, “growing up gay and having to suppress one’s identity [could] cause post traumatic stress disorder. Anybody experiencing trauma or abuse from childhood [may] ultimately engage in self-harming behaviors.”

Thomas Loveless, a professor at Rutgers University in New Jersey, interviewed a group of 18 gay men who had sought out HIV for a 2013 paper, “Gay Men and the Intentional Pursuit of HIV.” Loveless acknowledged the sample size was small, and that many of the men came from the same social circle, since several were found via word of mouth. But he still identifies several common characteristics. Many were men who’d faced traumas earlier in life: poverty, childhood trauma, or abuse. Addiction and struggles with substance abuse were also relatively common. Also cited was a desire to create a stronger bond with a HIV-positive partner. “HIV discordance was a barrier to true love and intimacy,” said the paper. “Only by taking on a lover’s HIV infection could they prove the unconditional love and devotion they shared with one another.”

Though there’s a substantial amount of online bug-chasing talk, it’s difficult to say how many men actually follow up and realize their desires in real life. One Twitter user, Richard, said he has gifted the disease “several times,” but admitted, “I get so many guys [who] hit me up to be pozzed but for most it’s more of a fantasy and a wank rather than having the guts to go through with it.”

Antiretroviral medication may have empowered some gay men to seek out HIV, but bug chasing flies directly in the face of the latest advancement in HIV-related healthcare, PrEP. The drug can reduce the chance of a HIV-negative person catching HIV by up to 99 percent if taken correctly. According to one estimate, at least 25,000 people in the U.S. were taking the drug by October 2015.

Despite better drugs, the rate of new HIV diagnoses hasn’t changed much since the mid ’90s. And men who sleep with other men continue to contract HIV in greater numbers than other groups. In 2014, 29,418 men who have sex with men became infected with HIV, the CDC reported, almost three times the number of heterosexuals who contracted the disease.

Offering an explanation for the infection numbers, the GMHC’s Sanchez echoed a sentiment from the 1990s. “The reality is for most people HIV is no longer a death sentence, so everyone is risk-assessing differently,” she said, “which is why we have seen more people not using condoms constantly.”

Bug chasers are a comparatively tiny group within the larger gay community, and many of them prefer not to talk to the media or academics about their activities, making it difficult to come to a consensus about what, if anything, might deter them. But because several bug chasers and gift givers are openly discussing their desires with one another on social media platforms, that could be about to change.

Hewes, one of the men who spoke to Vocativ online, said he is hoping to go on HIV prevention medication, as soon as he can get a job that helps him afford health insurance. But first, he said, he’d make good on all his arrangements with chasers he’d agreed to “gift” in the near future.