Rat on a Plane Reveals Hidden Risks of Global Pathogen Spread
BERLIN – A rat discovered aboard an aircraft has become an unlikely case study in the rapid, global dissemination of pathogens, according to research published September 10, 2025, in Scientific Reports. The rodent, found on a flight, carried Staphylococcus aureus bacteria with genetic markers suggesting transmission between humans and rats – and the potential for international spread.
Researchers, led by Dr. Ulrich, investigated the rat for known zoonotic diseases like hantaviruses, leptospirosis pathogens, and rat hepatitis-e virus, but found none present. However, the discovery of Staphylococcus aureus in the rat’s nose and intestine proved a surprising find. While the strain wasn’t multi-resistant like the feared hospital germ MRSA – which causes thousands of fatalities annually in Germany alone – it contained human-specific genes for immune defense and showed near-identical genetic makeup to strains found in people in Europe and North America.
“This shows that rats absorb our pathogens – and possibly return,” said Dr. Ulrich. “This bacterium is thus an indication of earlier transmissions between humans and rats.”
The research highlights how easily pathogens can traverse continents via both infected people and animal “fellow travelers.” Researchers emphasize that rats should be considered “active actors in the global network of pathogen distribution,” capable of traveling from locations like Dubai to Miami to Berlin within 24 hours, effectively transporting bacteria and viruses across continents.
“This was a wake-up call,” Dr. ulrich stated. “He showed how vulnerable our networked world is towards hidden pathogens,but also that science can provide practical solutions.”
The study was conducted by a team at the German Center for Infection Research e. V. (DZIF) and is available online: https://www.nature.com/articles/s41598-025-13199-6.