为了解四川省兔出血症病毒2型（rabbit hemorrhagic disease virus type 2，RHDV2）的流行情况及分子遗传变异特征，采集全省范围内的7 525份样品，其中发病兔场肝脏组织样品117份、环境拭子样品243份，受监测兔场血液样品3 340份、环境拭子样品3 825份，采用商品化荧光RT-PCR试剂盒，对以上样品进行RHDV2检测；对筛选出的12份肝组织阳性样品进行RHDV2 VP60基因RT-PCR扩增、测序和遗传进化分析。结果显示：RHDV2流行无明显季节性，各养殖品系家兔均有RHDV2感染，哺乳仔兔、幼兔、怀孕哺乳母兔死亡率分别为25%~60%、18%~45%、9%~30%。发病兔场肝脏样品RHDV2阳性检出率为88.89%（104/117），环境样品为46.09%（112/243）；受监测兔场全血样品RHDV2阳性检出率为25.99%（868/3340），环境样品为16.29%（623/3825）。12份阳性样品的RHDV2 VP60基因序列长度均为1 740 bp，核苷酸序列同源性为98.4%~100%，在系统发生进化树上独成一簇；与国内外参照毒株的VP60基因序列核苷酸同源性为93.7%~100%，编码的氨基酸序列同源性为95.7%~99.8%。结果表明：RHDV2已开始在四川省流行，需要加强检疫，重视饲养管理工作；其VP60基因序列出现了一定程度的变异，但遗传演化相对稳定。本研究补充了国内RHDV2的分子流行病学信息，也为该病的相关防控研究和控制对策制定提供了参考。
In order to investigate the prevalence and molecular genetic variation of rabbit hemorrhagic disease virus type 2（RHDV2）in Sichuan Province，a total of 7 525 samples were collected across the province for RHDV2 detection by commercial RT-PCR kits，including 117 rabbit liver tissues and 243 environmental swabs from the infected farms，as well as 3 340 blood and 3 825 environmental swabs from the monitored farms. 12 positive liver tissues were screened for RT-PCR amplification，sequencing and genetic evolution analysis of RHDV2 VP60 gene. The results showed that no obvious seasonality was observed in the prevalence of RHDV2，and all breeds of rabbits could be infected，the mortality rates of neonatal rabbits，young rabbits and pregnant or lactating rabbits were 25% to 60%，18% to 45% and 9% to 30%，respectively. The positive rate was 88.89%（104/117）in liver tissues and 46.09%（112/243）in environmental swabs from infected farms，25.99%（868/3 340）in whole blood and 16.29%（623/3 825）in environmental swabs from monitored farms. For 12 positive samples，the length of RHDV2 VP60 gene sequence was 1 740 bp，and the nucleotide sequence homology was 98.4% to 100%，which formed a single cluster in phylogenetic tree；their nucleotide homology with the reference RHDV2 VP60 gene sequence was 93.7% to 100%，and the encoded amino acid homology was 95.7% to 99.8%. In conclusion，RHDV2 had started to spread across the province，for which quarantine and feeding management should be strengthened；and its VP60 gene sequence varied to a certain extent，but its genetic evolution was relatively stable. The molecular epidemiological information related to RHDV2 was supplemented by the study，which also provided a reference for the development of relevant prevention and control measures for the disease.