Some of the world's rarest big cats are under threat from a virus carried by dogs, a wildlife expert has warned.
John Lewis, director of Wildlife Vets International, said there was evidence that Indonesian tigers were at risk from the canine distemper virus.
The virus used to be found mainly in dogs but seems to have evolved to infect animals like seals and tigers.
Infected animals usually develop breathing problems, have seizures, and display unusual behaviour.
Threat to tigers
It is a big threat to tigers because it can make them lose their fear of humans. Infected tigers may walk into nearby towns and this puts them in danger.
Dr Lewis explained: "It puts them at big risk because they lose their fear of poachers or they bring themselves in situations of conflict, such as playing with traffic."
Dr Lewis plans to work with Indonesian vets to develop a strategy to protect the nation's tigers from the virus.