With any luck, the myth of Patient Zero being responsible for HIV/AIDS in the US will finally be completely put to rest.

Gaétan Dugas may not be a household name for most, but he’s the man who has largely been blamed for HIV/AIDS in the United States. Dugas was a gay French-Canadian airline steward who worked for Air Canada in the 1970s and 1980s. Because his work involved a significant amount of travel and because of the number of his sexual contacts, a 1984 study linked him to some other early cases (though it could not necessarily prove a direct line of infection).

Dugas came to public attention in 1987, thanks to Randy Shilts’ book And the Band Played On. Shilts’ book was a wake-up call to the public and a devastating indictment of the inaction motivated largely by homophobia that crippled the US government’s response to the disease. It also introduced Dugas as Patient Zero. Shilts specifically named Dugas (who died of AIDS-related kidney failure in 1984) as “play[ing] a key role in spreading the new virus from one end of the United States to the other.” Shilts goes on to describe Dugas as practically a sociopath, knowingly infecting other men and taking a perverse pleasure in doing so. After Shilts’ book was published, many other media outlets jumped on the story, including this 60 Minutes piece. The movie version of the book, produced by HBO in 1993, further cemented Dugas’ ignominious legacy. The story even pops up on page 21 in Malcolm Gladwell’s 2002 book, The Tipping Point.

Last week, Nature published an article by scientists based in the US, UK, and Belgium that used genetic sequencing to prove that HIV appeared in the US earlier than previously suspected and that it arrived by a different path than previously assumed. They found that the virus had been circulating in the US since 1970 and likely arrived in the US from Africa via Haiti on multiple occasions. This research even shows that the moniker Patient Zero arose from typographical confusion; the initial study in 1984 that sought to identify linkages among HIV infections designated Dugas Patient O (for “outside Southern California), but was later misread.

This is not the first research to cast doubt on the idea of a Patient Zero causing HIV/AIDS in the US. A 2007 PNAS paper argued that the virus had been in the US since the late 1960s or early 1970s, but hadn’t infected enough people to be noticed. A 2003 study showed that HIV did not arrive in the US in a single instance, but rather entered the country repeatedly through independent channels. Other researchers noted that Dugas actually helped epidemiologists trace some of his sexual partners and flew to Atlanta to donate blood samples.

The notion of an index case—the first patient within a given population with a particular illness or condition noticed by health authorities—is a valid and useful tool for epidemiologists, but not for the sake of vilification. Dr. Michael Worobey, one of the co-authors of the Nature article, told a press conference, “No one should be blamed for the spread of a virus that no one even knew about.”

The case of Patient Zero and Dugas has important lessons for global health. First, it shows how stigma can undermine efforts to address an outbreak. Blaming Dugas reinforced prejudices against gay men and discouraged governments from taking action. This sort of stigma can lead to calls for quarantine and isolation (or, as William F. Buckley famously suggested in 1986, tattooing the buttocks of gay men). When I read Shilts’ book for the first time in the early 1990s, I was both appalled at the US government’s inaction and scared what this would mean for me as a teenager just coming to terms with being gay. Rather than encouraging people to come forward to seek treatment or learn about a disease, this further pushes them away—particularly among groups that are already marginalized within society. We saw this most recently in Liberia during the Ebola outbreak, where security forces quarantined the West Point neighbourhood and then shot at protesters. Instead of stopping Ebola’s spread, these actions further separated local communities from the government and encouraged mistrust.

Second, delayed responses exacerbate outbreaks. This goes beyond Dugas, but speaks to the same issues of blame and singling out particular communities. In 1982, a reporter asked US Press Secretary Larry Speakes about AIDS and what the government was doing about it. Rather than talking about any sort of national response (or, if he was unfamiliar with the disease, telling the reporter he’d get back to him), Speakes laughed and made jokes. Reagan himself did not mention AIDS until 1985 and made no speech about AIDS until October 1987. By that time, the US already had more than 59,000 AIDS cases and nearly 28,000 deaths from the disease. There were people within the US government taking the disease seriously, but the silence from the president’s bully pulpit meant that these efforts received too little money and too little public attention.

Third, we cannot separate the science from the politics. In comparing the US’ response to Ebola and Reagan’s response to AIDS, Laura Helmuth argues that governments should “act based on science rather than superstition, xenophobia, victim-blaming, and panic.” On the one hand, this is absolutely correct. On the other, we cannot simply wish the political dimensions of a disease outbreak away. The story of Patient Zero resonated, in part, because it reinforced existing narratives and stereotypes about gay men. Dugas became a symbol, and this symbol had a direct effect on government responses. Rather than wishing the politics away, we need to challenge those prejudices and narratives that limit responses to disease outbreaks. If the politics won’t go away, then policymakers need to be ready to confront the politics head on.