Researchers in Germany say a review of fatal encephalitis cases in Bavaria has found that more than twice as many as previously known were tied to a rare animal-borne virusGermany's Bernhard Nocht Institute for Tropical Medicine.
Borna disease virus 1, or BoDV-1, is normally found in horses, sheep and other mammals. It was first identified as the cause of severe human encephalitis in 2018.
The virus is harbored by the bicolored white-toothed shrew and researchers suspect that infections are caused by contact with the animal's excrement. While natural human-to-human transmission has been ruled out, some cases resulted from organ transplants.
Symptoms of encephalitis include fever, severe headaches, speech and gait disorders that can lead to coma within days or a few weeks.
The researchers noted that while BoDV-1 has a very high death rate, “the absolute number of infections and hence the risk of infection is estimated to be very low.”
They said the main risk areas in Germany are the states of Bavaria, Thuringia, Saxony-Anhalt and parts of neighboring adjoining states.
Germany will require compulsory notification of BoDV-1 infections from March.