<abstract xmlns="http://www.w3.org/1999/xhtml">

<sec id="j_jvetres-2022-0048_s_005">
<h3>Introduction</h3>
<p>In May 2020, an outbreak of rabbit haemorrhagic disease 2 (RHD2) caused by the rabbit haemorrhagic disease virus 2 (RHDV2, GI.2) occurred in Sichuan, China. The acute onset and short disease course resulted in rabbit mortality as high as 42.86%. Currently, basic research on the aetiology and genetic characteristics of GI.2 is lacking in China.</p></sec>
<sec id="j_jvetres-2022-0048_s_006">
<h3>Material and Methods</h3>
<p>Pathological changes in various tissues from infected rabbits were investigated and the viral genome was characterised. This study used RT-PCR, histopathology and scanning electron microscopy to identify the pathogen in samples from infected rabbits that had died. Phylogenetic trees were constructed based on whole genome sequence analysis, and recombination events were analysed.</p></sec>
<sec id="j_jvetres-2022-0048_s_007">
<h3>Results</h3>
<p>RT-PCR identified the presence of GI.2. Histopathology revealed liver cell necrosis and haemorrhaging into lung alveoli. Electron microscopy demonstrated spherical GI.2 particles that were 40 nm in size. The gene sequence length of the isolate was 7,445 bp (GenBank accession number MW178244). A phylogenetic analysis based on the genome of the isolated strain and 60 reference strains showed that the isolate was grouped together with GI.2 strain MT586027.1 in a relatively independent sub-branch. The results of the recombination analysis showed that the strain was recombined from the MT586027.1 (major parent) and MN90145.1 (minor parent) strains, and recombination breakpoints were at locations in the 2858–5137 nt range.</p></sec>
<sec id="j_jvetres-2022-0048_s_008">
<h3>Conclusion</h3>
<p>The results of this study extend our understanding of the molecular epidemiology of GI.2.</p></sec>
</abstract>

Introduction
In May 2020, an outbreak of rabbit haemorrhagic disease 2 (RHD2) caused by the rabbit haemorrhagic disease virus 2 (RHDV2, GI.2) occurred in Sichuan, China. The acute onset and short disease course resulted in rabbit mortality as high as 42.86%. Currently, basic research on the aetiology and genetic characteristics of GI.2 is lacking in China.

Material and Methods
Pathological changes in various tissues from infected rabbits were investigated and the viral genome was characterised. This study used RT-PCR, histopathology and scanning electron microscopy to identify the pathogen in samples from infected rabbits that had died. Phylogenetic trees were constructed based on whole genome sequence analysis, and recombination events were analysed.

Results
RT-PCR identified the presence of GI.2. Histopathology revealed liver cell necrosis and haemorrhaging into lung alveoli. Electron microscopy demonstrated spherical GI.2 particles that were 40 nm in size. The gene sequence length of the isolate was 7,445 bp (GenBank accession number MW178244). A phylogenetic analysis based on the genome of the isolated strain and 60 reference strains showed that the isolate was grouped together with GI.2 strain MT586027.1 in a relatively independent sub-branch. The results of the recombination analysis showed that the strain was recombined from the MT586027.1 (major parent) and MN90145.1 (minor parent) strains, and recombination breakpoints were at locations in the 2858–5137 nt range.

Conclusion
The results of this study extend our understanding of the molecular epidemiology of GI.2.

Detection of a new emerging strain of rabbit haemorrhagic disease virus 2 (GI.2) in China

Journal of Veterinary Research

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Introduction
In May 2020, an outbreak of rabbit haemorrhagic disease 2 (RHD2) caused by the rabbit haemorrhagic disease virus 2 (RHDV2, GI.2) occurred in...

Major parent	Minor parent	Breakpoints (nt)	P value
			RDP	GENECONV	BootScan	MaxChi	Chimaera	SiScan	3Seq
			MT586027.1^a	MN90145.1^a	2858and 5137	-	-	-	2.046×10⁻⁷	2.481×10⁻⁶	-	4.093×10⁻⁵

Detection of a new emerging strain of rabbit haemorrhagic disease virus 2 (GI.2) in China

Data publikacji: 14 wrz 2022

Zakres stron: 289 - 295

Otrzymano: 10 mar 2022

Przyjęty: 30 sie 2022

DOI: https://doi.org/10.2478/jvetres-2022-0048

Słowa kluczowe
China, rabbit haemorrhagic disease virus 2, whole genome sequence, genetic variation

© 2022 W. Chen et al. published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Recombination analysis of the SCCN04 isolate

Detection of a new emerging strain of rabbit haemorrhagic disease virus 2 (GI.2) in China

Data publikacji: 14 wrz 2022

Zakres stron: 289 - 295

Otrzymano: 10 mar 2022

Przyjęty: 30 sie 2022

DOI: https://doi.org/10.2478/jvetres-2022-0048

Słowa kluczoweChina, rabbit haemorrhagic disease virus 2, whole genome sequence, genetic variation

© 2022 W. Chen et al. published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Recombination analysis of the SCCN04 isolate

Słowa kluczowe
China, rabbit haemorrhagic disease virus 2, whole genome sequence, genetic variation