Remember Knut, the polar bear? Scientists now know why he died - and it's heartbreaking

Raa! Picture: Getty Images

It turns out Knut, the world’s most famous polar bear, also died one of the most unluckiest deaths.

You might remember back in 2007, when “Knutmania” was at its height.

The cute little cub was rescued from its mother, who rejected him after he was born at a zoo garden in Munich. He was hand-raised by a keeper at Berlin Zoo and within a year, he’d added about 5 million euros to its gate-takings – its most profitable year since it opened in 1844.

Knut’s popularity was boosted enormously first by animal rights activists saying he should have been killed, as the zoo “was violating animal protection legislation by keeping him alive”.

That sparked a worldwide rally from fans saying he had a bond with his keeper and the world went mad for watching the cub become an enormous bear. His first appearance on March 23, 2007, was even dubbed “Knut Day”.

Roar. Picture: Getty Images

Four years later, he died a very public and distressing death.

Up to 700 zoo visitors saw him collapse and back leg begin to shake. He began convulsing, and fell into the pool in his enclosure, where it is believed he drowned.

An autotopsy within a couple of months said a virus had caused encephalitis, which had swollen his brain. If Knut had not drowned, he would still have died. But they never figured out what the virus was – until now.

It seems one of the reasons they couldn’t figure it out was because, unfortunately for Knut, he’d caught a virus that has never been seen in non-humans.

Harald Pruess, from the German Centre for Neurodegenerative Diseases in Berlin, normally studies dementia in humans.

According to New Scientist, he and his team analysed samples of Knut’s cerebrospinal fluid and found “high levels of an antibody known to attack a glutamate receptor in the brain”. It’s the first sign of autoimmune encephalitis.

Sadly, autoimmune encephalitis:

“is treatable with immune-suppressing drugs, may be widespread among mammals. If Knut had been diagnosed, he might still be alive today.”

New Scientist reports the team is now investigating whether it’s also widespread among mammals, so if there’s any comfort to be had in Knut’s death, it’s that it might yet save his fellow animals from a similar fate.

Business Insider Emails & Alerts

Site highlights each day to your inbox.

Follow Business Insider Australia on Facebook, Twitter, LinkedIn, and Instagram.