'Patient Zero' Didn't Cause HIV Epidemic in US, New Study Finds

The man who was dubbed "patient zero" and long thought by many to have kick-started the North American HIV/AIDS epidemic actually had little to do with the spread of the virus, according to a new study published today the medical journal Nature that sheds new light on how HIV emerged in the U.S.

Using blood samples stored for decades and harnessing advanced methods to sequence the genome, the researchers, from multiple institutions including the University of Arizona, were able to reconstruct a comprehensive genome for eight patients dating back to 1978-1979.

The researchers used genetic methods to track and time the evolution of the genes of HIV and timed the emergence of HIV out of Africa to the Caribbean to 1967. As a result, they found that the American epidemic originated in the Caribbean in 1970 before arriving in the U.S.

After the disease arrived in New York City sometime between 1970 and 1974, the study data suggests that the disease quickly spread from New York City to the rest of the country. The HIV epidemic that emerged in San Francisco in 1978 was traced to a single "introduction" from New York City in 1976, according to the study findings.

In a further revision to the historical narrative, researchers also found that one patient often called "patient zero" in media reports likely had little to do with the spread of the disease, and that his infamous title was actually the result of a typo.

For many years, many had pointed to this "patient zero" as being instrumental in spreading the disease in various parts of the U.S. The book "The Band Played On," which documented the early days of the HIV crisis, complicated the story by naming the patient and identifying him as a French-Canadian flight attendant. Media coverage then used information from the book to "strongly" insinuate this man was the source of the North American HIV epidemic, according to the study researchers.

However, after examining his HIV genome, the study researchers found "patient zero's" virus to be "typical of U.S. strains at the time." Subsequent research and new information on the period of time the virus could remain dormant also revealed it was unlikely "Patient 0" had caused the HIV clusters to develop. The researchers found that this person had no "special role" in the epidemic.

Even the patient's title was also the result of a typo. In the records, he was actually labeled Patient "O" -- indicating the patient was "Out[side]-of-California."

While HIV can now largely be controlled with daily medication, it is still responsible for thousands of deaths every year in the U.S. An estimated 1.2 million people in the U.S. are infected with HIV and approximately one in eight are unaware they have the virus, according to the U.S. Centers for Disease Control and Prevention.

Though discrimination against people who have HIV still exists in some communities, groups are working to break through the stigma and advocates said they hope this study can be a catalyst for change.

Kelsey Louie, CEO of Gay Men's Health Crisis, an HIV advocacy organization, pointed out that HIV and AIDS groups have been calling for action rather than just assigning blame.

"Society, and in particular the media, were all too eager to cast blame on a single person, rather than reflect on the stigma they were creating and the lack of political will to actually do something about the disease," Louie told ABC News.

The federal government recommends that all people between the ages of 15 and 65 be screened for HIV, regardless of risk factors. Frequent testing is suggested for people at high risk, including men who have sex with men, people who use injection drugs, and those who have been diagnosed with a different sexually transmitted infection. People at risk for HIV can substantially reduce their risk through use of condoms, and for certain groups, taking a medication daily.

Dr. Alex Weller is a senior resident physician in internal medicine at Rutgers-New Jersey Medical School in Newark, New Jersey, and a resident at the ABC News Medical Unit.