Signs point to Haiti as U.S. AIDS source

A genetic analysis of 25-year-old blood samples has outlined a new map of the AIDS virus’s journey out of Africa, showing that today’s most widespread subtype first emerged in Haiti in the 1960s and arrived in the United States a few years later.

The analysis fills in a gap in the history of the virus, whose migration has been known in only a sketchy form from its origin in Africa in the 1930s to its first detection in Los Angeles in 1981.

Dr. Michael Gottlieb, an assistant clinical professor of medicine at the University of California, Los Angeles, and one of the original discoverers of acquired immune deficiency syndrome, said the analysis placed the AIDS virus in the United States nearly a decade earlier than previously believed.

“It’s pretty clear evidence for Haiti as a steppingstone,” he said. “The suggestion that the infection was further below our radar than I’d previously suspected is kind of unnerving.”

The analysis, published Monday in the Proceedings of the National Academy of Sciences, focused on a variety of the AIDS-causing virus, HIV, known as subtype B, which is the most prevalent form in most countries outside Africa.

Statistically, the researchers found a 99.7 percent certainty that HIV subtype B originated in Haiti, said Michael Worobey, an evolutionary biologist at the University of Arizona and senior author of the study.

Worobey surmised that the virus was brought to Haiti by workers who had gone to the Democratic Republic of Congo, formerly known as Zaire, after the country became independent in 1960. The virus appears to have been carried to the United States by Haitian immigrants sometime between 1966 and 1972, according to the mutation timeline.

Researchers have debated for years whether the U.S. epidemic came directly from Africa or through Haiti. They also have debated whether people from the United States exported the virus to Haiti through a sex-tourism trade that flourished in the late 1970s and early 1980s.