Genomic Characterization of a New Tembusu flavivirus from Domestic Ducks in Thailand

Tembusu virus (TMUV) namely KPS54A61 has spread in duck farms in many provinces in Thailand since 2010. The morbidity ranges from 15-30% and the mortality ranges from 10-15%. All infected ducks exhibit nervous signs including ataxia and paralysis. TMUV was successfully isolated from the brain and spinal cord of infected ducks by using C6/36 and Vero cells, but the typical cytopathic effect (CPE) was presented in the Vero cells only. Phylogenetic analysis of the whole genomic sequence of our TMUV-KPS54A61 virus showed that it belonged to the Ntaya virus group of Flaviviridae and its genomic sequence was similar to that of Baiyangdian virus (strain BYD-1, isolated from infected ducks in China) with 98% identity. This is the first report of whole genomic sequence of TMUV isolated from domestic ducks in Thailand.