Characterization of Akabane virus (KV0505) from cattle in Korea

Akabane disease is caused by an arthropod-borne viral pathogen and leads to congenital abnormalities of the central nervous system in infected ruminants. One isolate, KV0505, showed cytopathic effect in Vero cells. The KV0505 isolate was obtained from plasma, which was collected from a cattle raised on Jeju Island in May 2005. Jeju Island is located near the southern part of the Korean peninsula. The isolate was confirmed as Akabane virus (AKAV) by immunofluorescence assay using AKAV specific monoclonal antibodies and reverse transcription polymerase chain reaction (RTPCR). Suckling mice inoculated with the isolate showed signs of paralysis and died within 10 days postinoculation. Comparisons of the KV0505 N gene sequence with 39 other known AKAV strains revealed nucleotide homologies ranging from 83.6% (MP496 strain) to 99.7% (M171 strain). When compared with the K-9 strain, which was isolated from a cow in Korea in 1994, the nucleotide sequence homology with the N gene was 99.7%. Thus, genes of the KV0505 isolate were closely related to those of the M171 strain, which were clustered into the Ic group of AKAV.