HIV Arrived In US From Haiti Earlier Than Believed
The most widespread HIV subtype outside Africa likely emerged inHaiti in the 1960s and arrived in the U.S. a few years later -- about10 years earlier than previously believed -- according to a studypublished Tuesday in the Proceedings of the National Academy of Sciences, the Los Angeles Times reports.
For the study, Michael Worobey, an evolutionary biologist at the University of Arizona,and colleagues analyzed five blood samples collected in 1982 and 1983from Haitian HIV/AIDS patients in Miami that had been frozen and storedby CDC (Chong, Los Angeles Times, 10/30). In addition, the researches examined genetic data from 117 early HIV/AIDS patients worldwide (Dunham, Reuters,10/29). The researchers examined two viral genes and compared theirsequences with viruses found worldwide, using HIV samples from CentralAfrica considered to be some of the earliest forms of HIV as abaseline.
The researchers then constructed a timeline of HIVdevelopment by measuring how much the genes in recent blood samplesdiffered from early samples. According to the study, samples fromHaitians were genetically the most similar to the African virus,indicating the Haitian viruses were among the earliest to branch off.The researchers found a 99.7% certainty that HIV subtype B originatedin Haiti, Worobey said.
Worobey concluded that the virus wasbrought to Haiti by Haitians who traveled to the Democratic Republic ofCongo after it became independent in 1960. He added that the virus wasthen carried to the U.S. by Haitian immigrants between 1966 and 1972 (Los Angeles Times,10/30). The researchers believe an unknown Haitian immigrant likelyarrived in a large U.S. city, such as New York or Miami, and the viruscirculated in the U.S. population and then to other nations before itwas discovered. The mutation timeline of the virus presented in thestudy places the virus in the U.S. about 12 years before the diseasewas recognized by scientists in 1981, Reuters reports (Reuters, 10/29).
Thestudy's findings confirm many scientists' suspicions that the virus wasimported to the U.S. from Haiti and subsequently spread to Australia,Canada, Europe and Japan, AFP/Yahoo! News reports.HIV/AIDS prevalence among Haitians living in the U.S. was 27 timeshigher than in the broader U.S. population in the early days of theU.S. epidemic, according to AFP/Yahoo! News. In addition, the researchers concluded that HIV spread from Haiti to Trinidad and Tobago, fueling the Caribbean epidemic (AFP/Yahoo! News, 10/29).
"Once the virus got to the U.S., then it just moved explosively around the world," Worobey said (AFP/Yahoo! News,10/29). Worobey added that there likely were "hundreds of thousands ofinfections" before HIV was discovered. Arthur Pitchenik, a studyco-author from the University of Miami,said the study "gives [scientists] more clear insight into the historyof" the HIV/AIDS pandemic and "what path the virus took" (Reuters, 10/29).
Worobeyadded that the study did a "good job of settling the debate" overwhether the virus arrived in the U.S. from Africa or Haiti. "This showsquite clearly that the data is really only consistent with aHaiti-first origin," Worobey said. Beatrice Hahn, a virologist at the University of Alabama-Birminghamwho was not involved with the study, said the study's "calculations areas good as the currently available methods allow." Hahn cautionedagainst blaming the spread of HIV/AIDS on Haitians or Central Africans."These viruses are fairly clever, and they have to survive. They willfind niches. ... You realize chance events play a very important role,"Hahn said (Los Angeles Times, 10/30).
The Miami Herald onWednesday examined how the study's findings have "stoked controversyamong researchers and Haitians" by "reopening deep wounds over themedical community's role in perpetuating a stigma against people fromthe island" (Tasker/Charles, Miami Herald, 10/31).
Reprinted with permission from kaisernetwork.org. You can view theentire Kaiser DailyHIV/AIDS Report, search the archives, and sign up for email delivery at kaisernetwork.org/email . The Kaiser Daily HIV/AIDS Report ispublished for kaisernetwork.org, a free service of The Henry J. Kaiser FamilyFoundation.