March 17, 2008
Putting bugs on the map
By Carol Clark
Growing up in Jerusalem, Uriel Kitron was fascinated by bugs, maps and world explorers. He has managed to combine all three interests in his academic career. As a specialist in spatial epidemiology, Kitron uses geographic information systems (GIS) to create maps that pinpoint disease agents and their vectors, including insects, ticks, bats and other creatures.
“My father worked in the Israeli justice department, but I didn’t want to be a suit and tie guy,” says Kitron, who joined Emory in January as professor and chair of the Department of Environmental Studies.
He never needs to pack Armani for his global fieldwork, which involves everything from catching birds in mist nets to tracking the dreaded assassin bug. He even has to trap the occasional skunk.
“It helps if you put a piece of cloth over the cage,” Kitron advises anyone involved in skunk removal. “When it’s dark, a skunk usually will not spray you.” He adds that you should work in a group, just in case. “If it happens to everybody, you don’t notice it as much. It’s like eating garlic.”
Kitron comes to Emory from the University of Illinois, where he was co-director of the Center for Zoonoses Research. His ongoing projects include studies of Lyme disease and West Nile virus in the U.S.; malaria and schistosomiasis in Kenya; malaria and filariasis in Papua, New Guinea; dengue fever in Peru; and Chagas disease in Argentina.
“I’m especially interested in learning why we have a disease here and now and not there and then,” he says, summing up the ecological approach to his work.
Chagas disease, for instance, is caused by a parasite transmitted to humans and other animals mainly by the blood-sucking assassin bug, which lives in the thatched-roofed homes of some indigenous communities.
On his computer, Kitron demonstrates how his research team solved the mystery of why Chagas disease returned to a remote village in northern Argentina, after a bug-spraying program had eliminated it. The researchers used GIS technology to combine satellite photos of the village with other data and developed a multi-layered picture, including every livestock corral and house, along with the number and location of people and animals.
“In a way, we mapped every dog, every pig — every bug, even,” Kitron says.
Through the database, they could trace the return of the disease through the village and pinpoint the origin of the “super spreaders” — a pig corral. Further investigation determined that after the homes were sprayed, some of the bugs retreated to the corral where they managed to survive and regroup.
The researchers developed new parameters for bug-spraying campaigns by the local health authorities, to include animal corrals as well as homes and extend one-half kilometer around the village. “Our goal is to come up with disease intervention strategies that make the best use of limited resources,” Kitron explains.
A key part of his work is forming good relationships with the communities where he works, he adds. That means understanding the culture and helping people improve their lives in ways that fit their financial means and belief systems.
“I feel that there is a big gap in disease study, in terms of the medical and natural sciences and the social sciences,” he says. “We really need to develop more interdisciplinary approaches.”