STAGGERING DISEASE IN CATS - ISOLATION AND CHARACTERIZATION OF THE FELINE BORNA-DISEASE VIRUS

A Borna disease virus (BDV)-like agent was isolated from the central n ervous system (CNS) of cats with a spontaneous non-suppurative encepha lomyelitis ('staggering disease'). In contrast to the rabbit-adapted B DV strain V, which can be propagated in several primary and permanent cell cultures, the cat virus grew only in embryonic mink brain cells. Infection of adult Wistar rats with feline brain tissue material did n ot result in clinical disease during a period of 5 months, nor in grow th of infectious virus in the brain. However, using the brain suspensi on of a newborn rat inoculated with feline brain tissue material, it w as possible to induce typical Borna disease (BD) in four adult rats. T his indicates a possible adaptation of the cat virus during passages i n rats. By the use of an RT-PCR technique, BDV-specific RNA could be d etected in a majority of brain samples from diseased cats. BDV-specifi c antigen was demonstrated in feline CNS samples both by immunohistoch emistry and ELISA. However, the amount of BDV RNA and BDV antigen was less in the cats as compared to horses with BD, providing further supp ort for the notion that a distinct feline BDV strain exists.