Three men have died after they contracted a virus from squirrels in Germany.
After being bitten or scratched by the animals, the men developed encephalitis and died a few months later.
The illness they suffered causes fever and difficulty walking.
Experts are studying the dangers of squirrels and earlier this year the European Center for Disease Prevention and Control warned people not to feed or get close to them.
The threat of contracting an illness from squirrels still remains low.
Dr Marc Siegel, a professor of medicine at NYU Langone Medical Center, told HealthDay: ‘It’s likely that bornavirus, commonly found in horses and sheep was present in the squirrels that scratched these men, causing the neurological and behavioral symptoms.
‘It is possible this virus could spread to other squirrels and occasionally to humans, but we wouldn’t see sustained spread, as there is no evidence of spread from human to human.’