It's "Patient O," Not "Patient Zero"

In the early 1980s, young gay men started coming down with unusual and deadly illnesses, which were eventually attributed to a mysterious immune deficiency—the condition that would come to be known as AIDS. At the end of 1981, around 300 cases of the condition were reported. By the time HIV was discovered in 1984, there were nearly 8,000 AIDS cases in the U.S. alone. Throughout this horrific epidemic, one mystery nagged: who had unleashed this deadly disease? Who was North America's first HIV carrier? It's not who you think.

Finding the Source

That's what scientist William Darrow set to find out. In 1981, the CDC asked him to find out why gay men were dying from this strange illness. He caught wind of the fact that some early AIDS victims had been lovers, cluing him into the idea that the disease might be sexually transmitted. He began interviewing AIDS patients about their sex lives, and happened upon three who all named the same lover: a flight attendant from Canada. That man was Gaetan Dugas, who has since been immortalized — and made infamous — in countless books and movies about the AIDS epidemic as "patient zero": the "evil" man who brought AIDS to North America.

"O" vs "0"

The only problem is that Dugas wasn't patient zero, as in "the first patient." He was patient O, as in "a patient from outside of California." To maintain the privacy of the men in his study, Darrow identified them with a code that included their patient number and the city they lived in. For example, those in L.A. were patient LA1, patient LA2, and so on. Dugas was the only patient outside of the study area, so he was patient O.

This is more than just semantics: a 2016 study in Nature found DNA evidence that Dugas was not the first case of AIDS in North America. In fact, by the time Dugas contracted HIV, there were already thousands of Americans infected. A simple misreading of his patient code has unfairly etched this Canadian flight attendant in history as the villain of the AIDS epidemic. Learn more about the HIV/AIDS pandemic in the videos below.

Where Did HIV Come From?

Find out how scientists determined that so-called "patient zero" wasn't the first to spread the deadly virus in North America.

AIDS Activist Larry Kramer on the Patient Zero Myth

Hear this LGBT icon talk about the latest news about the virus's origins.

The Science of HIV/AIDS

Discover how HIV invades the body and turns into AIDS.

Written by Ashley Hamer November 14, 2016

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