New research suggests wild amphibians may play a significant and underappreciated role in hosting and facilitating the spread of infectious diseases.

Scientists say the interferon systems of amphibians -- the protein-signaling systems that govern the immune system and fight disease -- is both unique and largely ignored by the scientific literature.

"Amphibians have a previously unknown complexity within their antimicrobial interferon system, which is highly and differentially responsive to influenza infections," Yongming Sang, research associate professor of anatomy and physiology at Kansas State University, said in a news release. "This suggests the need to study the possible role of wild amphibians as overlooked reservoirs-end hosts for influenza and other zoonotic pathogenic infections."

To get a better idea of the role of amphibians in the spread of disease, researchers subjected frog cells to a variety of influenza A viruses and other zoonotic pathogens. Scientists used viral strains isolated from chickens, horses and pigs.

The viral strains isolated from pigs showed a higher level of infectivity in the frog cells than other isolates, suggesting the relationship between pigs and amphibians may serve as a significant viral vector prior to a strain's jump from animal to human.

"We learned that amphibians as typical insect eaters could also be critical vectors for other arthropod-borne viruses and intracellular bacteria, which are a major health threats in both humans and animals," Sang said. "The coordinated regulation of protective responses mediated by interferon signaling in both vector animals and end hosts may provide an integrated approach to discern critical components of conserved, cross-species innate immune mechanisms."

Sang believes further research into the immune signaling systems of amphibians could reveal ways to combat the spread of infections diseases.

The new research was published this week in the journal Scientific Reports.