The study is the first to perform a combined analysis of viral distribution and the local immune response in human BoDV-1 encephalitis. Based on four fatal cases, we observed a regionally accentuated viral load, particularly in the basal ganglia and hippocampus, which was associated with lymphocytic infiltration as well as microglial and astrocytic activation. The findings indicate a pronounced innate immune response alongside comparatively limited adaptive immune signatures, which may contribute to insufficient viral clearance and severe tissue damage.
