Roads, roadlessness, and Rotovirus in southern coastal Ecuador

December 6, 2010

Jonathan Zelner, just finishing his PhD in Public Policy and Sociology, reflects on the role of social connectedness in reducing risks of disease and the implications for the development of northern coastal Ecuador.

Worldwide, one billion people lack access to clean water and almost 37 percent of the world's population lacks access to basic sanitation. Every year about two billion people contract diarrheal disease, an affliction responsible for the death of 1.5 million children annually.


Jonathan Zelner

Jonathan Zelner

"Like most of the developing world, rural Ecuador is a place where gastrointestinal illness and diarrheal disease are important public health problems," says Ford School PhD student Jonathan Zelner, "—a place where people lack clean water and proper sanitation facilities." Zelner's research explores how gastrointestinal disease transmission in this rural South American region has been affected by recent government-sponsored development initiatives.

In 1996 the Ecuadorian government began building roads to link the southern Colombian border with the Ecuadorian coast, and in 2001 a road spanning the southern end of the Chocô rainforest near the Pacific Ocean was completed. These roads provide faster and cheaper transportation to the region and link previously remote villages to urban centers.

The construction of the new roads provided something of a "natural experiment," notes Zelner—an opportunity to better understand how rapid development impacts infectious disease transmission.

Zelner has been part of a multidisciplinary team—led by Dr. Joseph Eisenberg of the Department of Epidemiology at the U-M School of Public Health—studying disease, development, and community social connectedness in that once roadless area of northern coastal Ecuador. Zelner, who also earned a graduate certificate in Complex Systems during his time at Michigan, was tapped to join the research team because of his background in mathematical modeling of ecological and epidemiological systems.

The hub of the region that the team studied is the town of Borbón, which lies close to the coast just north of Quito. Borbón is at the center of trade and commercial activity, and is at the heart of three river basins that flow to surrounding rural villages. The new road connections meant rapid development for some villages in the region: more trade, transportation, communication, development and resources. But it also introduced problems, including resource extraction, increased social instability, and increased exposure to new pathogen strains. Other villages, not connected to the road system, remained remote.

So which villages were more susceptible to gastrointestinal illness and diarrheal disease in the wake of the development? Zelner's research suggests that the answer lies to a large degree in the density of social connections within the communities.

In sociological terms, the "social connectedness" of a community is determined by the network of interpersonal relationships among community members: who a person spends time with and talks about important matters with, how many close relationships a person has.

First, Zelner's research extended earlier findings from the project, showing that the villages more accessible to Borbón by road were more socially fragmented than the remote villages: more people lived alone and had very few social connections than in the villages left untouched by the new roads.

Next, Zelner discovered that it was in the remote communities—where residents were more socially connected with friends, relatives, and families—that the risks of gastrointestinal illnesses were minimized.

Although densely connected social networks are more likely to facilitate person-to-person transmission of diarrheal pathogens such as Cholera, Rotavirus, and Giardia, the dangers appear to be mitigated by the positives associated with high degrees of social connectedness. Why is that? The data suggest that these villages are also better at developing effective, high quality water treatment and sanitation systems, which prevent exposure to gastrointestinal pathogens in the first place.

The research findings are expected to help policymakers predict—and shape—the potential impacts of rapid development on rural communities.

Among the first people Zelner met at the U-M was the Ford School's own Professor Carl Simon, who until last year directed the U-M Center for the Study of Complex Systems (CSCS). Zelner was drawn to the interdisciplinarity of a complex systems approach. "What complex systems does is let you take something like infectious diseases and epidemiology and cross that with sociological perspectives on health," he says.

Zelner's dissertation includes his research in Ecuador along with two other papers about social connectedness and gastrointestinal infections, and he is set to defend in December. After graduation, he will start a joint postdoctoral fellowship at Princeton University and the Research and Policy for Infectious Disease Dyanmics (RAPIDD) program at the Fogarty International Center of the National Institutes of Health. This program is focused on developing models for the transmission and evolution of infectious diseases—models that can be used to help shape and implement effective policies and interventions for controlling those diseases.

Below is a formatted version of this article from State & Hill, the magazine of the Ford School. View the entire Fall 2010 State & Hill here.