The deadly Mers coronavirus has been isolated in a bat in Saudi Arabia, scientists report.
The virus was detected in a faecal sample taken from an Egyptian tomb bat, collected close to the home of the first known Mers victim.
The research is published in the journal Emerging Infectious Diseases.
But while scientists found a genetic match, they think it is unlikely that bats are responsible for passing the virus to humans.
Instead they think the virus is spreading from the winged mammals to other animals before it is reaching people.
Another piece of research was recently published in the journal Lancet Infectious Diseases, which suggested that this intermediary animal could be the dromedary camel.