As warm weather returns to Minnesota, so too do the ticks and mosquitoes—and with them, the risk of serious illness. For Matt Aliota, associate professor in the Department of Veterinary and Biomedical Sciences at the University of Minnesota College of Veterinary Medicine (CVM), that seasonal risk is a year-round scientific mission.

In Minnesota and beyond, diseases spread by ticks, mosquitoes, and other biting insects—known as vector-borne illnesses—are on the rise. Aliota is at the leading edge of work to understand, predict, and prevent their spread. Backed by two major National Institutes of Health (NIH) grants and recognized nationally as a rising expert in emerging viral threats, he’s helping shape the future of public health by unraveling the complex relationships between viruses, their hosts, and the immune systems in between.

Aliota, who holds a PhD in virology, was always interested in science. But he was first introduced to the specialty he’s so passionate about by happenstance.

 “In college, I needed a job for beer money,” he says. “So I started working in a lab that studied mosquitoes—and I quickly learned that mosquitoes have a major impact on global health through the pathogens they transmit, especially on less privileged populations and those in the global south.”

And while he may not have anticipated it then, his desire to make a difference for those impacted by vector-borne diseases has come to have even more universal bearing. As climate change, habitat shifts, and global travel expand the ranges of disease-carrying mosquitoes and ticks, they bring viruses into contact with new human and animal populations. That includes people, pets, and wildlife in Minnesota.

“The inspiration for the research questions that my lab asks comes from the real world,” Aliota describes. “We try to make observations about how viruses are having an impact, and then we come back to the lab to design experiments that can help us better understand—and therefore predict and control—those natural phenomena.”

Monitoring a growing public health threat

One major focus of Aliota’s work is Powassan virus (POWV), a tick-borne illness that’s gaining traction in parts of the U.S., including in the Great Lakes and Northeast regions. With support from a five-year, $3.5 million NIH grant, Aliota is building foundational knowledge about how the virus spreads and evolves—critical insight for anticipating and preventing future outbreaks.

Though still relatively rare, POWV can cause severe illness, including brain inflammation, paralysis, and in some cases, death. With no vaccine or treatment currently available, the virus represents a growing public health concern—especially in states like Minnesota and New York, where cases have risen in recent years.

Aliota’s project combines field and lab-based studies to understand how POWV spreads and evolves. 

“This has been an understudied virus to date, so we need basic information to really understand how big of a problem it’s going to be,” he says. 

His team investigates how genetic variation in both the virus and tick populations affects transmission and disease outcomes. They also work to identify the wildlife hosts, such as small mammals, that act as natural reservoirs and maintain the virus in the environment by infecting new generations of ticks that feed on them, even when human cases are rare.

To support this ambitious research, Aliota collaborates closely with the Minnesota Department of Health, which he’s working with to expand surveillance efforts, collecting infected ticks across the state. In New York, he partners with the New York State Department of Health, which maintains a robust archive of POWV samples and an active tick collection program. Additional collaborators include the Wadsworth Center, which provides expertise in studying tick-virus interactions and virus genetics, and the University of Pennsylvania, which supports research into tick population genetics.

Led by Aliota, this multi-institutional team is uncovering the ecological and evolutionary forces behind POWV’s emergence—and laying the groundwork for future disease prediction, prevention, and control.

Understanding how past infections shape future immunity

A second NIH-funded project, conducted in collaboration with researchers from the University of Wisconsin–Madison and the University of California, Berkeley, investigates how immunity to one flavivirus—a group of vector-borne viruses primarily spread by mosquitoes, including Zika, dengue, and yellow fever—can influence how the body responds to another. 

Flaviviruses represent a growing global health threat. Diseases like dengue, Zika, yellow fever, and West Nile virus infect hundreds of millions of people each year, often in regions with limited healthcare infrastructure. And as with other vector-borne diseases, the range of the mosquitoes that transmit them is increasing, along with the likelihood of outbreaks in new areas. Yet despite their widespread impact, many flaviviruses remain poorly understood, and limited vaccines and treatments exist. That makes foundational research like Aliota’s all the more urgent.

With $5.4 million in funding over five years, Aliota and his colleagues are exploring how exposure history affects immune responses. This is especially relevant in the case of viruses like dengue and Zika, where immunity is a double-edged sword. In some cases, it protects—prior dengue infection can reduce the risk of severe Zika disease, for example. In other cases, it can make future infections worse—a phenomenon known as antibody-dependent enhancement (ADE), where the immune system’s prior response backfires, like sending in the wrong troops and worsening the battle instead of winning it. 

This is true for dengue, which is a complex of four different viruses called serotypes. Previous infection with one serotype can sometimes intensify the effects of an infection with a different serotype, and now evidence suggests that previous Zika virus infection can intensify the effects of a dengue virus infection too.

Aliota and his collaborators are exploring how the number and order of past infections influence the immune system’s response to future flavivirus exposure. They’re particularly interested in a virus called Spondweni (SPOV), Zika’s closest known relative, and how immune responses to Zika and SPOV do—or don’t—cross over.

To dig deeper into these complex immune dynamics, the team draws on detailed data from a long-running pediatric dengue study in Nicaragua, paired with findings from carefully controlled laboratory research. They’re studying which antibodies are produced, how they function, and how these responses shape viral replication and disease severity.

“Ultimately, we can use this information to design better vaccines, and find other ways to reduce people’s risk of getting sick,” Aliota says..

Building a healthier future through discovery

In addition to his grant-funded research, Aliota plays an active role in several major collaborative efforts. He is a Fellow of the American Society of Tropical Medicine and Hygiene and a key contributor to a global working group led by the University of Minnesota’s Center for Infectious Disease Research and Policy (CIDRAP), which sets research priorities for Zika virus. His growing national profile as a media source further underscores the urgency and broad relevance of the issues he studies.

The insights emerging from these efforts couldn’t be more timely. As shifting environments and global movement reshape the landscape of infectious disease, understanding how viruses evolve, spread, and interact with both hosts and one another is critical. This kind of foundational knowledge equips public health systems to respond faster, more effectively, and with greater precision, before outbreaks become crises.

This work reflects a One Health approach, which recognizes that animal, human, and environmental health are deeply interconnected. By embracing that complexity and by building strong national and international partnerships, Aliota is helping translate foundational science into meaningful public health solutions. As tick season begins, his work serves as a powerful reminder that the best defense against emerging disease threats is preparation—and that preparation begins with science.

“The threats are changing, but so are our tools,” Aliota says. “We’re not powerless, and that’s what science is all about: turning uncertainty into answers.”