If you’re a dog owner, there’s a good chance that every month, you give your four-footed friend an antiparasitic treatment. For decades, these preventative medications have protected pets from parasites.

Such treatments are pillars of responsible pet ownership, said Dr. Lacy Sukovaty, director of Missouri State University’s School of Agricultural Science and Conservation. Without these preventative medications, dogs are vulnerable to serious illness — which creates danger for humans, too. “Hookworms and roundworms have zoonotic potential,” she said. “This means they can cause problems for people.”  

And once a parasite crosses over into humans, unpredictable things happen.

“When a parasite moves into a host species that’s different from its usual host, it doesn’t behave the same way.”

For example, hookworms can migrate through someone’s exposed skin, causing uncomfortable lesions. And if hookworms migrate through a person’s optic nerve, they can trigger irreversible vision loss.

Parasites with potential to evade prevention

In recent years, drug-resistant hookworms — which can evade monthly preventatives and common deworming treatments — emerged in Australia. Sukovaty wanted to know if they’re present in the Ozarks. 

She began by looking at national data on parasite prevalence. At first glance, the numbers for southwest Missouri appeared reassuring, with hookworm prevalence around 2%. But, Sukovaty said, samples for this data overwhelmingly came from veterinary clinics. These samples were likely collected from pets receiving veterinary services — the kind of dogs that are probably getting monthly preventatives from their doting owners.  

Sukovaty was curious about parasite prevalence in our region’s total canine population, including dogs that can’t rely on an owner’s care.  

To capture a more complete picture, Sukovaty reached out to community partners, such as the Polk County Humane Society (PCHS). It was a common-sense collaboration, one with clear upsides for both organizations. “Our work benefits both student development and the broader community by improving animal care practices,” Sukovaty said.  

She asked PCHS personnel to take samples from dogs when they arrived at the shelter. This data revealed hookworm prevalence of about 10%, five times higher than the data that was sourced from veterinary clinics. 

When Sukovaty gained a clearer picture of hookworm prevalence in the Ozarks, she wanted to know more about the hookworms themselves — specifically, whether they demonstrate signs of resistance to antiparasitic drugs. To find out, she asked shelter staff to take additional samples, after the dogs received treatments. These samples were taken 10 days after intake, and staff continued to take samples for the duration of a dog’s time at the shelter.  

Some clinical data indicates that drug-resistant parasites may already be present in the Ozarks, Sukovaty said, but more testing is needed. Since parasites are transmitted from one dog to another, “It will provide a clearer, more accurate picture of exposure risk,” she said. “When you’re out walking your dog, what might they be exposed to?” 

After that, she’d like to investigate how these parasites evade treatments that have been effective in the past. “There’s current research into genetic markers that may be enabling the resistance,” she said. “If the resistance turns out to be genetic, what does that mean for prevention, going forward?” 

Implications outside the lab 

In addition to her career as a faculty member, Sukovaty has professional history as a veterinarian, so she’s cognizant of the ways her research might influence owners’ relationships with their pets. She doesn’t want to inhibit affectionate interactions between people and their dogs.  

“It’s important to know that for most of the parasites we encounter, monthly preventatives work,” she said. “And they are very important for public health, not just the animal’s health.” This is particularly true in homes with young children, senior citizens and people who have compromised immune systems.  

And it’s possible that environmental strategies can play a role in prevention. In the future, Sukovaty would like to compare parasite prevalence in dogs at urban shelters to the data she’s gathered from rural shelters, like PCHS. Some common city materials, like concrete, may create barriers and help block transmission, she said.  

Opportunities for students

Whenever possible, Sukovaty includes students in her research. Two graduate students in the Master of Science-Agriculture program, Mattie Cobban and Diana Summitt, made key contributions to the investigation into parasite prevalence in our region. Both students went on to present their contributions in research forums.  

For Sukovaty, these research opportunities aren’t just about building students’ critical thinking and technical skills; they’re also about building relationships. “Because you spend so much time in the lab together, you create lasting connections,” she said. “Even after graduation, students often reach out to share their successes — and sometimes, to ask for advice. We all need a mentor when life throws you a few bumps.” 

Further reading

Learn about animal science and conservation at MSU

• Story by Lucie Amberg
• Photo by Jesse Scheve