Knut, grown up and as a cub in 2007
Michael Kappeler/Colourpress/JPI; Markus Schreiber/AP
04/01/2011 AT 01:55 PM EDT
04/01/2011 AT 10:05 AM EDT
Nearly two weeks after the sudden death of Knut the polar bear
on March 19, the final necropsy results were made public: Knut, who walked in circles before seizing up and falling into the water in his enclosure at the Berlin Zoo, drowned.
While drowning was the immediate cause of death, experts who examined his body concluded that the underlying cause was encephalitis, or a swelling of the brain brought on by an infection.
The nature of the infection is unclear, explained Claudia Szentiks, the pathologist who led Knut's examination, although it was probably caused by a virus. Other possible causes such as rabies, botulism and a prion infection (i.e., mad cow disease) were ruled out.
According to reports, Knut carried the infection for quite a while, and it was so severe that it likely would have killed the bear eventually.
"Given the massive scale of the inflammation, Knut would probably have died sooner or later," explained Szentiks.
It is unclear whether the three female polar bears that had frequent contact with Knut are also infected. However, the expert team will continue doing tests on Knut's body, according to reports in Spiegel Online
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