Increased pathogenicity and aerosol transmission for one SARS-CoV-2 B.1.617.2 Delta variant over the wild-type strain in hamsters  

作　　者：Xinghai Zhang Shaohong Chen Zengguo Cao Yanfeng Yao Junping Yu Junhui Zhou Ge Gao Ping He Zhuo Dong Jie Zhong Jing Luo Hongping Wei Huajun Zhang 

机构地区：[1]State Key Laboratory of Virology,Key Laboratory of Special Pathogens and Biosafety,Wuhan Institute of Virology,Chinese Academy of Sciences,Wuhan,430071,China [2]University of Chinese Academy of Sciences,Beijing,101409,China [3]Hubei International Travel Healthcare Center(Wuhan Customs Port Outpatient Department),Wuhan,430040,China

出　　处：《Virologica Sinica》2022年第6期796-803,共8页中国病毒学（英文版）

基　　金：supported by China Natural Science Foundation (82150201)

摘　　要：During the two-year pandemic of coronavirus disease 2019(COVID-19), its causative agent, severe acute respiratory syndrome coronavirus 2(SARS-CoV-2), has been evolving. SARS-CoV-2 Delta, a variant of concern, has become the dominant circulating strain worldwide within just a few months. Here, we performed a comprehensive analysis of a new B.1.617.2 Delta strain(Delta630) compared with the early WIV04 strain(WIV04) in vitro and in vivo, in terms of replication, infectivity, pathogenicity, and transmission in hamsters. When inoculated intranasally, Delta630 led to more pronounced weight loss and more severe disease in hamsters. Moreover, 40%mortality occurred about one week after infection with 10^(4)PFU of Delta630, whereas no deaths occurred even after infection with 10^(5)PFU of WIV04 or other strains belonging to the Delta variant. Moreover, Delta630outgrew over WIV04 in the competitive aerosol transmission experiment. Taken together, the Delta630 strain showed increased replication ability, pathogenicity, and transmissibility over WIV04 in hamsters. To our knowledge, this is the first SARS-CoV-2 strain that causes death in a hamster model, which could be an asset for the efficacy evaluation of vaccines and antivirals against infections of SARS-CoV-2 Delta strains. The underlying molecular mechanisms of increased virulence and transmission await further analysis.

关 键 词：SARS-CoV-2 B.1.617.2 Delta variant Syrian hamsters PATHOGENICITY Transmission 

分 类 号：R373[医药卫生—病原生物学]