A UA researcher who led a groundbreaking study about the history of the HIV/AIDS outbreak says his investigation — which made international news this week — took eight years of sleuthing.
"I've been in touch over the years with anyone who might have relevant samples. I've gotten to know several older Belgian scientists who did work in the Congo back in the day," Michael Worobey, a University of Arizona assistant professor of ecology and evolutionary biology, said in an interview Wednesday.
Worobey's research indicates the HIV/AIDS pandemic began around 1900, decades earlier than first thought.
"The really intense work has been since I came to the UA. I had a postdoc student from Oxford who is an expert on ancient DNA," Worobey said. "I decided I wanted to do my own lab work, and you need a special set of conditions to do it successfully — it has to be ultra-clean and ultra-sterile. It has been quite an amount of work, the whole time behind the scenes, so it's nice to see it come to fruition."
All day Wednesday, Worobey fielded calls and e-mails from around the globe.
"It's a bit scary when the inbox fills up, but at the same time I like having the opportunity to go beyond talking to my peers in the HIV research world," he said. "It's nice to have people paying attention to the work we're doing. It's a nice contrast to the years of plugging away."
Worobey, 35, has been at the UA since 2003 and focuses his research on understanding the origins, emergency control and pathogen of retroviruses, including HIV.
He has spent several years studying how to recover the fragmented pieces of viral DNA and RNA from archival specimens, to track when the virus first jumped from chimpanzees to humans.
He is doing an ongoing study of where, when and how AIDS viruses have crossed into humans, and whether ancestral viral sequences could be useful in developing vaccines against HIV or hepatitis C.
Worobey said he began his work during a trip to the Congo in 2000 while he was a doctoral student at Oxford collecting samples on AIDS-related viruses. His findings about HIV, featured in the current issue of the journal Nature, are part of his investigation into the evolution of AIDS-related viruses in wild-living African primates using non-invasively collected samples.
"There is a lot more work to be done. It's almost like we've opened up a new avenue of research, to go back and get these sequences. It's really the beginning of this work," he said.
The research indicates the most pervasive global strain of HIV began spreading among humans between 1884 and 1924, suggesting that growing urbanization in colonial Africa set the stage for the HIV/AIDS pandemic.
Worobey doubts more research will show the spread began any earlier than the late 19th century.
"I think we're pretty close to where it's going to end up. It's possible but unlikely we'd find some branch on the evolutionary tree that went deeper," he said. "It's not likely a coincidence that the emergence of cities in Africa opened the door to the age of AIDS. I kind of doubt it was circulated before that point. I'd love to be proven wrong, it would be interesting. But I do think we're closing in."
His research was co-sponsored by the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health, and the David and Lucile Packard Foundation.
Worobey, a native of Salmon Arm, British Columbia, earned his doctorate from the University of Oxford in 2001, and completed postdoctoral research in the Department of Zoology at Oxford. He holds a bachelor's degree in biological sciences from Simon Fraser University in Canada and was a Rhodes Scholar in 1997.
In an interview with UA News this week, Worobey emphasize that the research has implications for reversing the current AIDS epidemic.
"If HIV has one weak spot, it is that it is a relatively poorly transmitted virus. From better testing and prevention, to wider use of antiretroviral drug therapy, there are a number of ways to reduce transmission and force this virus back into extinction," he said. "Our results suggest that there are reasons for such optimism."