Three Simbu serogroup viruses, Peaton virus, Sathuperi virus
, and Shamonda virus (SHAV), were identified in Japan during the past 2 decades and have been suspected of being involved in congenital defects in calves (8).
SBV has been identified as most related to Sathuperi virus, and for the small and large segments, Shamonda virus segments show the highest sequence identity.
The emergence in Japan of Sathuperi virus, a tropical Simbu serogroup virus of the genus Orthobunyavirus.
Results of full-genome and serologic investigations indicate that SBV belongs to the species Sathuperi virus and is a possible ancestor of the reassortant Shamonda virus.
Additionally, results of recent investigations on complete N and M genes and partial L genes of SHAV, Douglas virus (DOUV), and Sathuperi virus (SATV) suggested that SBV is a reassortant consisting of the M segment from SATV and the S and L segments from SHAV (9).
To enable comparative sequence analysis and phylogenetic investigations, we determined almost full-length S-, M-, and L-segment sequences for 9 Simbu serogroup viruses belonging to 5 species (Table 1): SHAV, Peaton virus, and Sango virus, species Shamonda virus; DOUV and SATV, species Sathuperi virus; Aino virus and Shuni virus, species Shuni virus; Sabo virus, species Akabane virus; and Simbu virus, species Simbu virus.
On the other hand, the high sequence identity of all SBV genes to SATV and DOUV indicates that SBV belongs to the species Sathuperi virus.