First isolation, in-vivo and genomic characterization of zoonotic variegated squirrel Bornavirus 1 (VSBV-1) isolates

Variegated squirrel bornavirus 1 (VSBV-1) is a recently discovered zoonotic virus that causes severe encephalitis in humans. VSBV-1 was found in a fatal human infection, and screening tests revealed that captive exotic squirrels were involved. Variable squirrels (Sciurus variegatoides) and red-tailed squirrels (Sciurus granatensis) have been tested positive for VSBV-1. The authors successfully isolated the virus from the brain and kidney of VSBV-1-infected squirrels. The isolated VSBV-1 sequence had more than 99% similarity to the original squirrels-based viral sequence. Lewis rats inoculated with VSBV-1, regardless of age or route of infection, showed no clinical signs and did not shed the virus. Viral RNA was detected in the cerebrum, cerebellum, and spinal cord of neonatal rats inoculated with VSBV-1 in the brain. As a result, VSBV-1 may infect Lewis rats, but further studies are needed before it can be used as an experimental model.
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