Borna disease virus 1 infection causing fatal meningoencephalomyelitis in wild European hedgehogs in known endemic areas, Germany, 2022 to 2024

Herein, we report Borna disease virus 1 (BoDV-1) infection in seven wild European hedgehogs (Erinaceus europaeus) from an endemic area in Germany. BoDV-1 causes encephalitis with a fatality rate of more than 90% in domestic mammals and humans. Currently, the bicolored white-toothed shrew (Crocidura leucodon) is the only known reservoir host. As hedgehogs are distant relatives of shrews and often cared for by humans, the cases raise concern regarding a potential zoonotic risk. All of the hedgehogs that tested positive for BoDV-1 had succumbed to neurological disease and exhibited severe polio-predominant lymphoplasmohistiocytic meningoencephalitis. However, due to the detection of viral antigens in non-neural cells in one animal, it cannot be completely excluded that some infected hedgehogs shed the virus. Although direct BoDV-1 transmission is known to be inefficient, our results emphasize the necessity of hygiene measures when handling hedgehogs, especially those with neurological signs from BoDV-1-endemic regions.