image: Montana State University microbiology researchers Reetika Chaurasia, left, and Patrick Secor examine petri dishes in a lab Wednesday, Feb. 26, 2025, in Bozeman, Mont. MSU photo by Colter Peterson
Credit: MSU photo by Colter Peterson
BOZEMAN – Funding from the National Institutes of Health will allow a Montana State University research team to deepen explorations into a disease that is posing an increasing threat in the U.S.
Lyme disease is a bacterial infection transmitted by ticks, and nearly 90,000 cases in the U.S. were reported by the Centers for Disease Control and Prevention in 2023. The most prevalent tick-borne disease in the Northern hemisphere, it can be passed from ticks to other animals, such as mice or deer, or to humans via tick bites, and can cause long-lasting syndromes for those who become infected.
While Lyme disease has historically been found mostly in the northeastern United States, climate change has expanded the geographic range where infected ticks are found to include North Dakota and other Western states.
“It's made its way all the way from the East Coast,” said Patrick Secor, an associate professor in MSU’s Department of Microbiology and Cell Biology in the College of Agriculture. “Vaccination does work for Lyme disease, and that's where we're hoping to come in.”
While previous Lyme disease vaccines have proved effective, Secor said, most versions require frequent boosters, making them less effective if people don’t receive them as often as they should. Secor’s lab will use an NIH grant of $2.8 million over five years to study adaptations in the bacterium that causes Lyme disease, aiming to better illuminate how it circumvents its host’s immune system to establish infection.
That disease-causing bacterium, called Borrelia burgdorferi, is itself the host to viruses called bacteriophages. Viruses are one of the most abundant biological entities on Earth, said Secor, and the bacteriophages that infect B. burgdorferi may serve an important role in disease development. The bacteriophages transfer genetic material between bacterial strains to disguise the bacteria’s presence and make reinfection possible in a host that has already been exposed. Secor published research last year in the journal PLOS Pathogens that outlined genomic analysis of bacteriophages, exploring how they move genetic material.
“If you think about the mice that are the reservoir species for Borrelia and the ticks that are the vector, those populations are pretty geographically constrained,” said Secor. “For the bacteria to survive, they have to go back and forth between the tick and the mouse. But the mouse they go back into has probably already been exposed, so the bacterium needs to essentially change its spots so that it can avoid the mouse’s immune response. That’s why we think it's important for these bacteria to swap genes around.”
Genetic analysis has established that the viral genomes in the Borrelia bacteria were around 95% identical, but they include a variable region that encodes proteins that vary how the bacteria appear to the host’s immune system. Secor’s team will investigate which genetic material is being swapped between bacterial strains by the phages with the aim of discovering more effective targets for Lyme disease treatments.
“We want to see which strains get through the immune system. It's like a bottleneck,” Secor said. “The stuff that gets through is important. It allows the bacteria to get around the immune system and establish an infection, so it's a way for us to use biology to point toward new things like vaccine antigens for Lyme disease.”
Secor was born and raised in the Gallatin Valley and received both his undergraduate and doctoral degrees from MSU. After postdoctoral research at the University of Washington in Seattle, he established a lab at the University of Montana that transitioned to be housed at MSU last fall semester.
For the NIH-supported work, Secor and assistant professor Reetika Chaurasia will collaborate with Scott Samuels, a Lyme disease scientist at UM, and with UM’s Center for Translational Medicine, to apply their findings to the development of more effective Lyme disease therapies and treatments. The work will involve numerous undergraduate and graduate student researchers, and for Secor, continuing his scientific career at his alma mater has already proven to be fulfilling.
“One of my favorite things about the department is that I can walk down the hall and interact with other faculty or students in other labs, and the same is true for my students,” he said. “There’s a tight sense of community here, and that's something that I really enjoy.”