A team of researchers led by Penn State has been awarded $4 million from the National Science Foundation to investigate the elements that lead to the spread of Lassa virus from rodents to humans in Nigeria.
Lassa virus (LASV) is a member of the arenavirus family of viruses that can cause Lassa fever, an acute viral hemorrhagic illness, according to the World Health Organization.
The team will use their data to map, at a broad scale, the risk of LASV spilling over from rodents to humans — for example, a map showing when and where people encounter infected rodents across Nigeria or West Africa. Additionally, the researchers hope to learn more about how climate change or changes to land use could affect spillover risk in the future.
Sagan Friant, assistant professor of anthropology at Penn State, said she’s hoping the research will help them better understand the ways humans influence the ecology and evolution of infectious diseases.
“By incorporating humans into our models, we can better understand how our behavior and interactions with our environment — like hunting, farming practices or settlement patterns — can play a role in constructing entire disease systems,” Friant said. “It’s becoming more and more critical to understand the intricacies of how to prevent and respond to outbreaks of LASV and other rodent-borne diseases. For example, monkeypox is another rodent-borne disease that has had a recent global increase. If we can build a mechanistic understanding of how we affect spillover, we can build more effective strategies to mitigate disease. We can also make more informative risk maps to help target our interventions.”
The team also includes researchers from Tulane University, the Zoological Society of London and the African Center of Excellence for Genomics of Infectious Disease.
According to Christina Harden, graduate student in Penn State’s Intercollege Graduate Degree Program in Ecology, the work will aim to understand how normal, day-to-day human activities — like hunting or growing food — create or diffuse the risk of people contracting Lassa.
“We hope to do this by looking closely at how these activities are linked to rodent reservoir behavior and their Lassa virus dynamics,” Harden said. “Our approach situates LASV as something that is influenced by human activities both locally and at scale, rather than something that just happens to humans that overlap with the reservoir.”
Ottar Bjornstad, distinguished professor of entomology and biology and J. Lloyd & Dorothy Foehr Huck Chair of Epidemiology at Penn State, said the project will be an opportunity to collaborate with other interdisciplinary teams.
“Most important spillover diseases are either from bats, like the current COVID pandemic, or rodents, like hantavirus pulmonary syndrome and hemorrhagic fever,” Bjornstad said. “This exciting international collaboration focusing on Lassa fever — another rodent-borne zoonosis — will involve scientists from the U.S., U.K. and Nigeria and will shed critical new light on transmission at the animal-human interface.”
The researchers said that eventually, they hope their work could lead to better health outcomes in areas affected by the virus.
“Ultimately, this is a disease of poverty that has a huge impact on many lives across West Africa,” Harden said. “Figuring out some of the where, when, how and why people get LASV could illuminate a path towards better disease prevention. The greatest potential impact, to me, is fewer cases of Lassa Fever.”