Abstract
Rabbit haemorrhagic virus (RHDV) is a highly infectious and fatal
pathogen to rabbits. Classic RHDV is mainly pathogenic to adult rabbits;
however, it is not lethal to young rabbits. Since 2010, a RHDV variant
has become prevalent in Europe and the Australian continent. This
variant, which was named RHDV2 (GI.2/RHDVb), is highly infectious and
fatal to both adult and young rabbits; moreover, its host range is
broader than that of classic RHDV (GI.1/G1-6). In May 2020, the first
RHDV2 case in China was reported. Here, we report and describe the first
RHDV2 case in China. We amplified its complete genome sequence (named
SC20-01 strain). The phylogenetic tree showed that the SC20-01 strain is
mostly related to two strains isolated in Europe, which indicated that
it might have spread from Europe to China. Moreover, Recombination
Detection Program software showed that the SC20-01 strain is a G6/RHDV2
recombinant strain. Animal experiments showed that the SC20-01 strain is
a highly fatal pathogen to specific-pathogen-free (SPF) rabbits and
induces typical clinical symptoms of RHD. Our findings highlight RHDV2
emergence in China and its potential to spread widely. There is a need
for more attention on the RHDV2 threat in China and the development of
new diagnostic methods and vaccines for preventing the spread of RHDV2.