Global Food

Eliminating E.coli by changing human behavior

A few months after Madhura Vachon started working as a foodborne disease epidemiologist with the Indiana Department of Health, the unthinkable happened. A toddler became infected with E.coli while playing near his family’s sheep. He tragically died just days later. 

“That was really jarring for me as an investigator and that led me to focus my research on Shiga toxin‐producing E.coli,” said Vachon, who is now a PhD student in the University of Minnesota (UMN) School of Public Health’s (SPH) Division of Environmental Health Sciences. 

Humans can contract Shiga toxin‐producing E.coli bacteria from food, water, and animals, but Vachon’s research focuses on transmission from animals to humans. With funding and support from the MnDRIVE Global Food Ventures Research Fellowship, Vachon has been able to study whether or not people who have direct contact with farm animals have more severe clinical outcomes than people who get the toxin-producing E.coli from other sources. 

Shinga toxin-producing E.coli is particularly dangerous in children younger than 5 years old. The bacteria release a toxin that binds to receptors in the kidney, causing hemolytic uremic syndrome (HUS) and eventually kidney failure. 

“What I found was that yes, people were more likely to get HUS if they had direct farm animal contact versus other types of exposure. That means that the way people are getting it may make a difference in their clinical outcomes,” Vachon said. 

According to Craig Hedberg, PhD, a professor and Interim Division Head of the SPH Division of Environmental Health Sciences, who oversaw the research, showing that people who contract the bacteria through direct contact with an animal could have life-saving consequences.

“When physicians are trying to manage these cases, knowing that a kid with diarrhea has recently had an encounter with an animal at a farm or petting zoo may prompt them to manage that illness a little more aggressively than they otherwise might do since they need to have a higher suspicion that it may be related to exposure to E.coli,” Hedberg said. 

This new piece of information also helps researchers like Vachon better understand how to prevent Shiga toxin‐producing E.coli from being ingested by humans in the first place. 

“The animals can carry the bacteria without being sick themselves, so it’s really hard to know when they are carrying it,” said Vachon, whose secondary research focuses on influencing behavior, mainly handwashing, which can drastically reduce the risk of ingesting the bacteria. 

Her laboratory was a hometown favorite: the Minnesota State Fair. 

On a mission to understand what most influenced people’s handwashing behavior, Vachon polled fairgoers using a series of images. Sometimes the photos depicted social influences, such as a person’s friends using the handwashing station set up in the barn. Other times, a fair staff member would direct them to wash their hands after interacting with the animals. She also explored how the position of the handwashing station, how many people were in line, and the presence of different types of signage influenced whether or not a person said they were likely to wash their hands. The outcome was having a blueprint for how barns at fairs can be better designed to align with what motivates people to wash their hands after interacting with the animals. 

Next, Vachon wants to test the amount of E.coli cows shed in different situations, and whether or not certain factors make cattle shed more bacteria regardless of the situation. 

“Other studies have shown that more stress causes more bacteria shedding in the animal’s stool,” explains Vachon, who also plans to explore whether regularly being around farm animals increases a person’s immunity to HUS.