Genetic testing on 1970s blood samples has shown that Gaetan Dugas, long vilified as an originator of the HIV/AIDS epidemic in the United States, was not the man responsible for spreading the deadly disease.

A study published in the journal Nature put together the genetic sequence of the HIV virus from archived blood samples of gay and bisexual men who were participating in a hepatitis B study at the time. Researchers then traced the genetic changes of the virus among men in New York and San Francisco. They found the HIV virus came from the Caribbean to New York City around 1970, starting the North American epidemic.

University of Arizona evolutionary biologist Michael Worobey led the study. "The outbreaks in California that caused people to ring alarm bells and led to the discovery of AIDS were really just offshoots of the earlier outbreak that we see in New York City," said Worobey.

Too late for Dugas

Dugas was much maligned after his death due to AIDS in 1984. Three years later, Dugas became known as "Patient Zero" in Randy Shilts' book "And the Band Played On." The work looked at the start of the AIDS epidemic in the United States and included a 1984 study by the U.S. Centers for Disease Control and Prevention that connected AIDS to sexual transmission in 40 homosexual men.

Dugas was noted in the study as "Patient O." As O's and zeros look similar, some researchers "began interpreting the ambiguous oval as a digit, and referring to 'Patient O' as 'Patient 0' (zero)," said public health historian Richard McKay, who was a co-author of the study. Shilts used this interpretation in his book, and Dugas' name was associated with spreading the virus in the country. Dugas worked as a flight attendant for Air Canada.

"This individual was simply one of thousands infected before HIV was recognized," said McKay.

The HIV virus is spread through the transmission of certain bodily fluids, primarily through sexual intercourse or sharing needles with an infected person. HIV often leads to AIDS, which has claimed more than 650,000 lives in the US.

kbd/gsw (AFP, Reuters)