A Canadian flight attendant long known as “Patient Zero” and blamed from bringing HIV into the US has been exonerated by new research published this week in the journal Nature that has found that the AIDS-causing virus had reached the States earlier than previously believed.
A team led by University of Arizona evolutionary biologist Dr. Michael Worobey genetically sequenced samples collected by early HIV-infected individuals and found that the virus likely came to America from Haiti in 1970 or 1971, according to NPR and the Los Angeles Times.
The virus went undetected by doctors for years, the report indicates, arriving in New York City from the Caribbean and circulating there for at least half a decade before an infected individual traveled to San Francisco, bringing the virus with him to the west coast. By the late 1970s, Dr. Worobey and his colleagues wrote, there were thousands of people infected with HIV.
So when a CDC investigation into the sexual activities of gay and bisexual men uncovered, in March 1984, that Canadian-born Gaëtan Dugas was at the center of a network of sexual partners responsible for helping to spread the disease, the immunodeficiency virus already had been here for more than a decade already. In short, he couldn’t have possibly been “Patient Zero.”
Disease was fairly widespread years before ‘Patient Zero’ diagnosis
Dr. Worobey and his colleagues conducted a genetic analysis which found that the most common strain of HIV traveled from the Caribbean to New York sometime around 1970, circulating there for approximately five years before it spread to other parts of the US after one infected man took it to California, analysis of samples originally collected to test for hepatitis revealed.
“There really is no question about the geographical direction of movement,” Dr. Worobey told the Times. He and his team found evidence of this spread by analyzing serum samples collected from gay men in New York and San Francisco in the late 1970s, which were tested for hepatitis (which was prevalent among homosexuals at the time) but not HIV, as it was not known to exist at the time. They found HIV-fighting antibodies present in the collected blood samples.
Specifically, 6.6% of the New York samples and 3.7% of the San Francisco ones contained HIV antibodies, and while that revealed the existence of the virus, it did not provide the scientists with any detailed information about the pathogen. So they searched for fragments of HIV RNA in the samples and managed to compile full virus genomes in eight of them, according to reports.
So while Dugas was instrumental in bringing HIV into the public consciousness, even flying to a CDC facility in Atlanta to donate blood and providing officials with a list of other men who may have been infected, according to NPR, he was not the man who brought the disease to the US. In fact, the new research reveals that by the late 1970s, as many as 7% of gay men in New York and 4% in San Francisco had already been infected – years before Dugas’s case came to light.
“To me, there’s something nice about going back and correcting the record. He has been blamed for things that no one should be blamed for,” Dr. Worobey told NPR. “Nobody should be blamed for the spread of a virus that nobody even knew about,” he added in an interview with the Times.
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