Since the age of five, Dr. Kevin Cummings knew he wanted to become a veterinarian. He grew up playing with his dogs and watching birds outside of Buffalo, New York. Pursuing his dream years later at Cornell’s College of Veterinary Medicine (CVM) and then in clinical practice, he was always most fascinated by cases of infectious disease.

Now an associate professor in CVM’s Department of Public & Ecosystem Health who has been teaching epidemiology and public health for the last 20 years, Dr. Cummings leads infectious disease research projects with dogs and dairy cattle, as well as wildlife and people, and he mentors MPH, veterinary, and graduate students who assist with data collection and analysis. Many of his current projects involve improving our understanding of the ecology and transmission of zoonotic enteric pathogens, many of which are multidrug-resistant. One of these pathogens is Campylobacter jejuni, which can cause gastrointestinal disease in dogs as well as people. In fact, a recent multistate outbreak of Campylobacter jejuni in people was traced to contact with puppies in pet stores.

“I like being able to straddle the fence between animal and human diseases,” says Dr. Cummings, who is dedicated to advancing One Health through his research, including questions related to antimicrobial resistance and foodborne disease. One Health is an approach that understands that human health is fully integrated with the health of the environment, including animals and plants. As the effects of climate change unfold and the human population increases, a One Health perspective is increasingly vital for solving complex public health problems in ways that are sustainable and long-lasting.

Salmonellosis is another infectious disease that impacts humans as well as livestock, pets, and wildlife. In an ongoing USDA-funded study, Dr. Cummings aims to improve diagnostic protocols in dairy cattle for a unique serotype of Salmonella bacteria called Salmonella Dublin, which is “host-adapted” to cattle, causes pneumonia in calves with high mortality, and is associated with higher hospitalization and death rates in humans. “We need more information on what makes animals more likely to become carriers,” says Dr. Cummings, who looks at how this multidrug-resistant pathogen is being introduced and spread across farms. “Virtually all strains [of Salmonella Dublin] in the Northeast have the same multidrug-resistant phenotype,” he says, which makes it difficult to treat. His team is using novel testing methods and sample types to comprehensively define Salmonella Dublin shedding patterns and transmission dynamics in dairy cattle, with the goal of improving diagnostic protocols and disease control strategies.

The emergence of COVID-19 is also a One Health issue closely linked to climate change, wildlife habitats, and animal food markets. “When the pandemic arrived, there was an obvious need to identify the factors driving transmission [among people] unique to a college campus,” recalls Dr. Cummings. He was sought at the time for his study design skills, which he teaches in the introductory “Epidemiology in Practice” course for MPH students. Dr. Cummings was able to work with Cornell’s robust surveillance systems to analyze data from over 1,600 students. While the results weren’t surprising—the strongest risk factors were recent attendance at parties and bars, recent travel, and living in a residence hall—the data are essential for educating university communities to help prevent future outbreaks. “In class, I ask students how they would have designed the same study,” he explains, “and we compare our ideas.”

Written by Audrey Baker