A team of researchers from the University of Minnesota's College of Veterinary Medicine (CVM) and Medical School has been awarded two five-year grants from the National Institutes of Health (NIH) totaling $6.7 million to study how certain viruses cause severe disease in pregnant individuals, and how to develop vaccines against these deadly and emerging viruses. The crucial work is focused on arenaviruses, such as Lassa virus and Junin virus, which are potentially pandemic pathogens and are particularly dangerous for pregnant individuals.

While Lassa and Junin viruses cause endemic infections in West Africa and South America, respectively, their potential for global spread is a significant concern. The World Health Organization has placed them on its "Blueprint" list of diseases requiring urgent research and development. Lassa virus is especially virulent during pregnancy, with maternal mortality rates reaching as high as 50 percent in the final trimester and causing exceptionally high rates of pregnancy loss.

Despite this, there is no established animal model to study the disease in pregnant individuals and, as a result, no approved vaccines or treatments. Therefore, one of the goals of the NIH-funded projects is to develop vaccines against Junin virus and related arenaviruses that can also cause severe hemorrhagic fevers in South America.

This significant federal funding comes after the team, led by CVM professors Yuying Liang and Hinh Ly, along with Craig Bierle from the Medical School, first proved their research concept using a competitive internal CVM grant. With that grant, they developed a groundbreaking animal model to study Lassa fever in pregnancy. This preliminary work was successful in replicating the disease's devastating effects, providing critical data that proved the concept and paved the way for larger federal grants.

"This effort exemplifies collaborative science and is made possible by the complementary expertise of our teams and our collaborators in intramural National Institute for Allergy and Infectious Diseases laboratories,” Bierle says.

With the new NIH funding, the research team will now delve deeper into the biological mechanisms behind the disease. They will explore how arenaviruses manage to infect the placenta and cause severe damage. They will also investigate how to combat them with new vaccines that use a harmless virus, developed in the Liang/Ly labs, to teach the body's immune system how to fight back.

“I’m excited to join this collaborative effort to advance research that will help protect people—especially pregnant women and their babies—from devastating arenavirus infections,” Liang says of the project’s next steps.

The research team’s work on Lassa and Junin viruses will provide a crucial model for understanding other known and emerging viruses that are already present in the U.S. and can also cause severe disease, including pregnancy-related complications. In addition, this research is critical for public health, as the potential for these viruses to spread is increasing with climate change and rapid globalization. Furthermore, because of the severe risk they pose, arenaviruses such as Lassa and Junin are considered bioterrorism agents by the U.S. government, underscoring the importance of this work for both national security and public health preparedness.

“This collaborative effort between laboratories in the College of Veterinary Medicine and the School of Medicine highlights how veterinary medicine research can directly inform and impact human health,” says Ly, who served as a principal investigator on both the internal and federal grants. “By studying the mechanisms of disease in relevant animal models and human tissues, we are paving the way for the development of innovative strategies to protect pregnant people and their offspring from the devastating effects of pathogenic viral infection.”