PMC

Cytopathic effect (CPE) of Vero cells caused by Usutu virus infection, 4 days postinfection (hematoxylin-eosin staining). A) Uninfected control, B) Usutu virus infected. bar = 100 µm.

Demonstration of Usutu virus antigen 3 days postinfection. Immunohistochemical (IHC) tests were performed by using a polyclonal antibody to West Nile virus, which cross-reacts with Usutu virus. A) Vero control; B) Vero infected; C) CR [define] (feline) control; D) CR infected; E) goose embryo fibroblast (GEF) [define] control; F) GEF infected; A,B) bar = 50 µm; C–F) bar = 100 µm. IHC staining.