he Intervector Exploratory Center, part of the Global Public Health Program at the University of Miami, is developing new strategies for controlling the transmission of mosquito-borne diseases in urban areas of Costa Rica, Trinidad, Israel, Egypt, and Kenya.

“Here in the United States, there is a link between the public health department and mosquito control,” Beier says. “In other countries we don’t see that.”

In the coastal city of Puntarenas, Costa Rica, Troyo takes the information she’s collected on dengue cases and begins plotting the distribution of the disease throughout the city. With the help of Douglas Fuller, associate professor of geography and regional studies in the College of Arts and Sciences, Troyo is using high-resolution satellite imagery to map the urban environment of Puntarenas—virtually.

“ This kind of imagery is revolutionizing the way we view urban environments,” says Fuller, who also is a specialist in geographic information systems (GIS) and remote sensing. “This is probably one of the first efforts to use high- resolution satellite imagery to address a key health concern like dengue fever.”

The imagery is remarkably sharp. Arrows on a deserted airstrip and cars on a highway are easily distinguishable. Fuller is the expert in image processing and analysis, while Troyo, the disease specialist, knows Puntarenas like the back of her hand. Together they can interpret most images on the computer screen.

“Obviously, we can see only the built or natural environment with this technology. We can’t tell if people are using bed nets or how they are discarding stagnant water around the house,” explains Fuller. “But it will give us a good indicator of areas that are likely to be susceptible to the disease.”

By overlaying the remote sensing data onto maps of the city, Fuller and Troyo can view the amount of vegetation or degree of urbanization in an area, extract such variables as building density by district, and then relate this epidemiologically to dengue fever cases. “It seems that the urban structure definitely determines the likelihood of dengue occurrence in certain parts of this area,” says Fuller.

The next phase is to validate some of the information gathered from the remote sensing data by returning to the study site and pinpointing the mosquitoes’ exact breeding locations. More importantly, the research will assist the Costa Rican Ministry of Health in targeting its future mosquito control activities.

In Curepe, Trinidad, ongoing surveys by researchers reveal that conventional mosquito control through use of insecticides has been ineffective. Surveys of homes found that the Aedes aegypti mosquitoes lay eggs in artificial water-holding containers that are thrown out as garbage by residents.

“We are now looking at translating knowledge into practice,” says Dave Chadee, a researcher at The University of the West Indies and a collaborator on the project who has found that residents do have some knowledge that mosquitoes are the vectors for dengue. “So now the job is to get them to do something about it.”

Researchers now are working in tandem with local groups such as the Rotary Club to educate the community as to how they can help solve the mosquito problem. And various measures are already in place, such as monthly visits to houses to inspect containers, to determine whether the educational campaign is working.

Malaria is another vector-borne disease with alarming statistics. An estimated 700,000 to 2.7 million people die of malaria each year, 75 percent of them African children, according to the CDC. In the coastal city of Malindi, Kenya, another urban study site, there are an estimated 40,000 cases of malaria in the city’s hospitals each year. At least four times a year, Beier says, one of the foreign investigators working in Kisumu, western Kenya, contracts malaria.

When Beier and international collaborators accompanied local mosquito control teams on their rounds in Malindi, they found that the control teams were pouring used engine oil on the surfaces of water to kill the mosquitoes (the oil suffocates the mosquito larvae). “Not only is this environmentally unacceptable, it makes a huge mess,” says Beier.

In Kisumu, preliminary surveys have indicated that humans have been actually promoting the spread of mosquitoes. The main culprit? Broken water pipes around the city. “Hooking water up to houses is very expensive here, so many people were breaking pipes at night to steal water. Water often seeps out into the grass, and the mosquitoes love it,” Beier says.

Disciplines like mathematics and mathematical ecology also play a critical role in this research. “We are trying to come up with a modeling framework that takes into account processes that are going on over multiple scales in terms of space, time, and organization,” says Robert Stephen Cantrell, UM professor of mathematics and an Intervector Exploratory Center investigator. “So we’re developing fairly complicated structures that blend both a mathematical tractability and an ecological and epidemiological interpretability.”

Ethics plays an equally important part, especially in an endeavor that confronts international governments about their practices. Kenneth Goodman, Ph.D. ’91, director of the University’s Bioethics Program and an investigator on the intervector study, emphasizes ways to conduct research without violating the rights of individuals or allowing them to be discriminated against. “We are keen to make sure that research that takes place is guided by sound principles and follows standard ethical rules,” Goodman says.

Health diplomacy, a burgeoning discipline that uses health research and collaboration to encourage resolution of conflict, is another area addressed by the Intervector Exploratory Center. Last March, the center and the Global Public Health Program cosponsored a meeting of 35 Jordanian, Israeli, and Palestinian mayors and municipal leaders in the Jordan River Valley to establish a continuing Mayors’ Forum to deal with common concerns in the areas of water, the environment, and public health. Mosquito-borne diseases like West Nile virus were high priorities.

“By the time we broke for lunch I saw people caucusing, but it wasn’t Israelis, Jordanians, and Palestinians separately. It was South Jordan Valley officials and North Jordan Valley officials discussing their common issues,” recalls Eugene Rothman, senior visiting research fellow at The Sue and Leonard Miller Center for Contemporary Judaic Studies and a project investigator, who chaired the session. “This was a perfect example of how different people, despite conflict, can and should cooperate.”

Collaboration of such diverse fields is what makes this project a model. “The whole idea in developing the framework for global public health is not building a center unto itself but really looking at a university without walls,” adds Sherri Porcelain, M.P.H. ’86, chair of the International Public Health Forum in the Department of International Studies, as well as a Miller School of Medicine adjunct faculty member. “If you really want to tackle today’s public health threats and challenges to human security, we need to engage the whole University community.”