Using a simple survey tool, a team of researchers has done what complex studies have failed to do -- provide data that identifies starting points for preventing diarrheal disease outbreaks in at least one region of Africa.
Diarrheal illness is a leading cause of disease and death in children under 5, and in HIV-plagued Botswana, it is a significant issue for those over 5 as well.
"Yet we still know little about the dynamics of this illness and other infectious diseases," said disease ecologist Kathleen Alexander, an associate professor of wildlife in the College of Natural Resources and the Environment and an affiliate faculty member with the university's Fralin Life Science Institute. "It is in these hard-hit areas that we know the least. Medical staff are so stretched that they can do little more than treat the sick and manage hospital functions during disease outbreaks."
One such area is the Chobe District of Botswana, where there are nine doctors for more than 23,000 people. The district's entire population is served by one primary hospital, three clinics, and 12 health posts. The 29-bed Kasane Primary Hospital is relatively unchanged since it was built in 1962.
"In such circumstances, waiting for complex studies of diarrheal disease outbreaks to be undertaken is just unrealistic," said Alexander. "How do we overcome these barriers? I wanted to see if we could use simpler tools in disease outbreak investigations that would engage the limitations of these resource-poor settings and allow us to begin to understand public health needs in these regions consistently and sustainably."
Alexander, working through the Center for African Resources: Animals, Communities and Land Use (CARACAL), a nonprofit organization she co-founded in Botswana, has been conducting a long-term study of human, wildlife, and environmental health in the Chobe District, an area that includes the Chobe National Park, forest reserves, and surrounding villages.
Alexander and Jason Blackburn, an assistant professor of geography and Emerging Pathogens Institute researcher at the University of Florida, undertook a study of diarrheal disease outbreaks in the Chobe District that relied only on the use of a simple questionnaire and existing hospital staff and infrastructure.
"The purpose of the questionnaire-based study was to try to find a way that governments in Africa like that of Botswana could begin to accumulate information on outbreak features that could be used even in the face of significant human resource, infrastructure, and technology constraints," Alexander said. "If we wait until there are more resources available to do sophisticated studies, they will never happen and we will continue to battle with diarrheal disease in much of Africa."
Using only local nursing staff, the questionnaire provided information that would otherwise not have been available, leading to immediate recommendations regarding control.
"This approach does not require increased human or economic resources or outside researchers, and it can give immediate insight into public health threats and disease outbreaks where this type of information otherwise would not be acquired. This is an important starting point," Alexander said.
Government medical staff assessed patients presenting with diarrheal disease during two diarrheal outbreaks in 2011 and 2012. They reported the name of the village, the patient's gender and age, and whether the patient was hospitalized. The staff also asked patients various questions including, for example, whether they boiled their water, if there was dirt in the water, if they had flush toilets, whether other members of the household had diarrhea, whether child patients were breast fed, whether water was piped indoors, if they stored water, and if water shortages occurred.
"A reasonable proportion of patients were surveyed during outbreak periods despite higher caseloads during outbreak periods," the researchers report in a studyin the August issue of BioMed Central Public Health.
In addition, using 2006-09 data provided by the Botswana Integrated Disease Surveillance and Response Program, the timing of recurrent diarrheal outbreaks was evaluated among patients under 5 years old.
"Outbreak periods appear to coincide with major rainfall and flood recession, identifying an important potential linkage between human health and environment," Alexander said.
"Information collected from patients affected with diarrheal disease supported the hypothesis that environmental factors are important in driving outbreaks in the region," she emphasized. "Water shortages and dirty water were also reported by patients in both of the 2011-12 outbreaks, identifying an important public health problem that can be immediately identified for action."
Despite water shortages, however, no one reported using the Chobe River for drinking water, countering the concern of the use of unsafe river water.