Emergence of rabbit hemorrhagic disease virus 2 in China in 2020
Running title: RHDV2 in China
Bo Hu#, Houjun Wei#, Zhiyu Fan#, Yanhua Song, Mengmeng Chen, Rulong Qiu, Weifeng Zhu, Weizhong Xu, Jiabin Xue, Fang Wang*
Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biologicals Engineering and Technology, Ministry of Agriculture, National Center for Engineering Research of Veterinary Bio-products, Nanjing 210014, China
*Corresponding author. Tel: +86 25 84390337; E-mail address: rwangfang@126.com
#These authors contributed equally to this work.
Summary:Rabbit hemorrhagic disease (RHD) is an acute fatal disease caused by thelagovirus rabbit hemorrhagic disease virus (RHDV), which was first reported in 1984 in China. Strains of two different genotypes (GI.1a and GI.1c) have been detected in China to date. In 2010, a new RHDV variant with a unique genetic and antigenic profile was identified in France, designated RHDV2, which rapidly spread throughout continental Europe and nearby islands. Here, we report the first outbreak of RHD induced by RHDV2 (GI.2) in rabbit farms in the Sichuan province of China. We conducted hemagglutination tests and phylogenetic analysis of the new RHDV isolate SC2020/04, which was identified as a non-hemagglutinating strain belonging to the RHDV2 (GI.2) genogroup. Considering the serious risk of RHDV2 to the Chinese rabbit industry, the circulation of RHDV2 in the population should be carefully monitored in China.
Key words: rabbit hemorrhagic disease virus, RHDV2,Lagovirus , rabbits, China
INTRODUCTION
China is highly ranked in the global rabbit industry, accounting for 43% of the worldwide slaughtered rabbits with 44% of the global share of rabbit meat output (Wu, Seema, & Huang, 2016). Rabbit hemorrhagic disease virus (RHDV) of the family Caliciviridae , genusLagovirus , causes high morbidity and mortality in rabbits. Over 90% of RHDV-infected adult rabbits die owing to fulminant hepatic failure within 3 days of infection (Park, Lee, & Itakura,1995). RHDV was first reported in China in 1984. However, a new RHDV-related virus designated RHDV2 was detected in France in 2010 (Le Gall-Recule et al., 2013), subsequently spreading to other countries in Europe, Australia, and Africa (Abrantes et al., 2013; Lopes et al., 2019; Mahar et al., 2018; Puggioni et al., 2013).
Based on phylogenetic analyses of RHDV VP60 sequences, RHDV is divided into classical RHDV (GI.1) and RHDV2 (GI.2). Two RHDV genotype strains are considered to be present in China, G2 (GI.1a) and G6 (GI.1c) (Hu et al., 2017). Here, we report a new RHDV isolate collected from three infected rabbits at farms in the Sichuan province of China in April 2020.