As a global health threat that continues to spread in under-resourced regions, cholera remains a stark example of how access to clean water, sanitation, and care can mean the difference between life and death.
Dr. Kirsten Wiens, assistant professor in the Department of Epidemiology and Biostatistics at Temple University’s College of Public Health (CPH), is working to improve how we detect, prevent, and respond to cholera outbreaks—especially those that fly under the radar of routine public health surveillance.
A bacterial illness transmitted through contaminated food and water, cholera causes severe dehydration and diarrhea, and affects an estimated 1 to 4 million people globally each year. “It affects people of all ages and can be especially severe among children with no prior exposure to the bacteria,” said Wiens. But even that range may be too low. A big challenge, she explains, lies in what we don’t see.
“Many cholera infections are mild or asymptomatic—so people wouldn’t necessarily seek medical care, further challenging surveillance,” Wiens said. “Also, healthcare access and testing capacity is limited in many places where cholera is most prevalent. As a result, passive surveillance systems miss a large share of the cases.”
Missing those cases isn’t just an academic problem. Vaccine supply is limited, and current distribution strategies rely in part on those global case estimates. “We have a good orally administered vaccine, but there’s not enough for everyone,” she said. “These estimates are used to help make really difficult decisions about where the vaccines should go.”
Dr. Wiens’ research is focused on closing that knowledge gap. With funding from the Gates Foundation and the National Institutes of Health, and in collaboration with researchers in countries like Bangladesh and the Democratic Republic of the Congo, she’s examining two critical areas:
- Estimating the share of acute watery diarrhea that is not treated in hospitals or clinics, especially in places where people can’t or don’t always seek care.
- Understanding the role of mild or asymptomatic infections in transmission. “Do they matter?” Wiens asks. “If so, how should that shape our public health responses?”
Next month, Wiens will travel to Senegal to meet with one of her international research teams. The visit, scheduled for early June, is part of an ongoing effort to ground her modeling work in the realities and nuances of on-the-ground health systems. “I’m really focused on identifying where and why cholera cases get missed, and how that should shape public health responses,” she said.
Wiens’ interest in infectious disease disparities began early. As an undergraduate, she spent a summer in a rural community in Panama where clean water was not readily available. “I saw firsthand how those disparities really shaped disparities in infection outcomes,” she said. “It shifted my focus to understanding what drives variation in infectious disease and susceptibility.”
Despite the hurdles of underreporting and limited resources, Wiens finds hope in the global collaboration driving her work. She also notes encouraging global attitudes toward vaccines. “Even though there are still issues with vaccine trust and access around the world, oral cholera vaccines are often well accepted, especially during outbreaks,” she said.
At CPH, Dr. Wiens continues to train the next generation of public health professionals, bringing together rigorous data analysis and an unwavering commitment to health equity. Her work reminds us that invisible cases can have very real consequences—and that understanding them is key to a more effective and just global health response.