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Parasites, Pigs and People in Peru


SPH Faculty Spotlight Series: Seth O’Neal, MD, MPH

Seth O’Neal is an assistant professor at the School of Public Health with some very remarkable research interests.  “It always surprises people to hear that tapeworms are responsible for about 1/3 of seizure disorders around world,” he said. Dr. O’Neal studies Taenia solium (the pork tapeworm), a cestode parasite that is transmitted between people and pigs. The larvae of the worm infect the human brain causing seizures, headaches, stroke and other neurologic problems. “It’s a tragic cycle in which impoverished rural communities are the most severely affected. The negative impact of the disease on human health and agriculture makes it that much more difficult for people in these communities to get ahead.”

Interrupting this cycle has recently become a priority at the World Health Organization, which is now pushing for efforts to control and eventually eliminate the disease. “We have reached a point where we now have reasonable diagnostic tests and medications, but we still don’t know the best strategies to apply these tools.” Dr. O’Neal’s research focuses on developing and testing new approaches in the rural settings where the disease occurs. Seemingly obvious solutions like corralling pigs or building latrines don’t always work.  “The world is a messy place. People’s priorities, beliefs and practices don’t always align with what we expect, so the trick is finding solutions that are both effective and acceptable within the communities.”

Most of his field work is done in Peru in collaboration with the Center for Global Health Tumbes at the Universidad Peruana Cayetano Heredia. There are upwards of 10,000 people involved in his studies across many villages in Peru. The work requires being immersed within these communities, going door to door to talk with people, collect samples, and provide treatment. It also involves getting up close and personal with pigs – catching and tracking them, drawing their blood and examining their tongues to find clusters of infection and neighborhoods with the most risk. “I am fortunate to work with an incredibly capable field team at our Center in Peru. They are the core of all the work we do.” The work requires a multidisciplinary and collaborative approach, so Dr. O’Neal works closely with other scientists, phsyicians, veterinarians and public health practitioners from around the globe.

A graduate of the Preventive Medicine Residency at OHSU, Dr. O’Neal has always had wide ranging interest in medicine and public health.  As a third year medical student through he spent a year in Brazil studying Leishmania (another parasite) through an NIH fellowship.  “It was a truly formative experience,” he said.  “I finally understood how I could merge my interests in clinical medicine, population health and basic science in the international setting.”

He left that fellowship determined to set-up a research program which would provide opportunities for other students to get hands-on mentored training in global health research here at OHSU. Through the SPH, he now mentors students from across the university taking them through the entire research process from identifying a research question, designing a study and collecting data in the field, to interpreting and reporting their results. Dr. O’Neal challenges all of his students to immerse themselves fully in the research experience, to travel to the field sites, and to work side-by-side with Peruvian students, professionals and community members to collect and analyze their data.

Dr. O’Neal is currently mentoring Ian Pray, a PhD in Epidemiology student and a graduate of the MPH program.  On Ian’s most recent trip to Peru, he used GPS collars and geospatial mapping software  to track pigs and to document their interaction with sites of open defecation in the villages.  Ian is interested in applying geospatial techniques to improve control interventions. Another recent graduate of the MPH program, veterinarian Robert Flecker, is currently in Peru evaluating biodigesting latrines as a potential control intervention, an approach which would also provide a clean and sustainable source of biogas fuel to reduce dependence on wood fuel. “Watching these students get excited and engaged though field research, and seeing the creative solutions they come up with for these challenging global health problems is truly wonderful. “