A large team of researchers linked to several institutions in Germany, Austria and Sweden have discovered a virus that causes a mysterious disease that is killing cats across Europe.
The research team has published the results of the study, which has not yet been peer-reviewed, in a bioRxiv preprint.
The disease known as ataxia has been known to afflict cats for almost half a century, but it became an even bigger problem in 2020 when the capybara, donkey and tree kangaroo were killed off in Germany.
Over the years, it has become associated with encephalitis in various animals.
More recently, the neurological disease mainly affected domestic cats. Symptoms include loss of the ability to retract claws, tremors, loss of limb control, and seizures.
Affected cats stagger as if drunk, giving the disease its distinctive feature (ataxia). The disease develops over a period of approximately two weeks, and there is still no known cure for the condition, and very few ancillary treatments for infected animals.
It is not known how long it takes for cats to die because most, if not all, of the victims died by “euthanasia” for humane reasons.
The initial study of the disease showed that it was caused by the Borna disease virus (a nervous syndrome in warm-blooded animals that causes behavioral problems and fatal accidents), but subsequent studies have not confirmed this theory.
In this new study, researchers are taking the disease more seriously as they try to find its source. They collected the brains of 29 euthanized cats in Germany, Austria and Sweden. The researchers scanned the entire brain for the presence of bornavirus DNA, but found nothing.
However, they found the rustrela virus in 28 brains. The rustrela virus is a relative of the rubella virus that infects humans.
The researchers concluded that their results strongly suggest that the rustrela virus is the cause of the disease in cats and note that the virus is commonly seen in wood mice.
They also speculate that it may also infect an unknown number of other mammals, possibly including humans.