Identification and molecular characterization of novel duck reoviruses
in central China, 2021: Implications for control programs
Abstract
Novel Duck
[reovirus](https://www.sciencedirect.com/topics/immunology-and-microbiology/reoviridae)
(NDRV) is an ongoing non-enveloped virus with ten double-stranded RNA
(dsRNA) genome segments that belong to the genus Orthoreovirus,
in the family Reoviridae. NDRV-associated spleen swelling and
necrosis disease have caused considerable economic losses to the
waterfowl industry worldwide. Since 2017, a significant number of NDRV
outbreaks have emerged in China. Herein, we describe two cases of duck
spleen necrosis disease among ducklings on duck farms in Henan province,
central China. Other potential causative agent, including Muscovy duck
reovirus (MDRV), Duck hepatitis A virus type 1 (DHAV-1), Duck hepatitis
A virus type 3 (DHAV-3), Newcastle disease virus (NDV), and Duck tembusu
virus (DTMUV), were excluded by reverse transcription-polymerase chain
reaction (RT-PCR), and two NDRV strains, HeNXX-1/2021 and HNJZ-2/2021,
were isolated. Sequencing and phylogenetic analysis of the σC genes
revealed that both newly identified NDRV isolates were closely related
to DRV/SDHZ17/Shandong/2017. The results further showed that Chinese
NDRVs had formed two distinct clades, with late 2017 as the turning
point, suggesting that Chinese NDRVs have been evolving in different
directions. In conclusion, this study provides an insight into the
ongoing emerged duck spleen necrosis disease, and a foundation for
developing of effective vaccine and control programs.