People and Animal Interactions Affect Water Quality

In northern Botswana's Chobe river region, the river is the only source of water during the dry season - a source of life, for humans and animals. But come change of season, it also seems to become a source of sickness.

Kathleen Alexander, associate professor of wildlife in Virginia Tech's College of Natural Resources and Environment, conducts research that evaluates coupled human and ecological drivers influencing water quality and the health of human and animal populations in the Chobe river region. She has lived in the area for most of the last 20 years. During this time she has noticed many of the residents regularly become ill with diarrhea at certain times of the year, coinciding with seasonal changes and with river flow.

"The river is the only source of water here in the dry season, so humans and animals cluster at its banks," Alexander said. "Water provides a connection between human and animal communities. Changes in water quality can profoundly change the health of all that use this resource."

Alexander has received a $250,000 National Science Foundation (NSF) grant to investigate the links between humans and animals as they influence water quality and, in turn, how water quality affects their health. She is using Escherichia coli (E. coli) to track the transmission of microbes through the river, wildlife, domestic animals, and humans. Her team, which includes a microbiologist, a water engineer, a medical geographer, and an anthropologist, is developing predictive models as an early warning framework for the government to use to protect humans, animals, and the ecosystem.

"We are studying the dynamics of how the activities and health of both humans and animal populations in the area are coupled in the system through water, and how land use and climate changes can influence this linkage."

The team includes Virginia Tech faculty members Monica Ponder, assistant professor of food science and technology and an affiliate of the Fralin Life Science Institute, and Leigh-Anne Krometis, assistant professor of biological systems engineering, both in the College of Agriculture and Life Sciences, as well as Jason Blackburn, assistant professor of geography at the University of Florida, and John Bock, professor of anthropology at California State University, Fullerton.

The project includes a large educational component working with various age groups, from schoolchildren to adults living in the study area. A water curriculum for use in local environmental clubs has been developed, and Botswana youth participate in project activities to gain experience in research and develop an appreciation of the importance of water management on rural livelihoods.

United States ambassador Michelle B Gavin visited the project at the end of November as a guest of Dr Alexander and her team. The ambassador also directed opened the Caracal Craft Centre in the Chobe Botswana NSF study site in recognition of the cooperation between Caracal, the Botswana Government and Virginia Tech. Caracal (Conservation of African Resources, Animals, Communities And Land use), is a local NGO and the in-country partner of the project.

For more on Alexander's health and water quality work in Botswana, visit the project's at

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