College of Medicine and Medical Research Institute, Chungbuk National University, Cheongju, Republic of Korea.
Zoonotic Infectious Diseases Research Center, Chungbuk National University, Cheongju, Korea.
Emerg Microbes Infect. 2021 Dec;10(1):152-160. doi: 10.1080/22221751.2021.1872352.
Cases of laboratory-confirmed SARS-CoV-2 reinfection have been reported in a number of countries. Further, the level of natural immunity induced by SARS-CoV-2 infection is not fully clear, nor is it clear if a primary infection is protective against reinfection. To investigate the potential association between serum antibody titres and reinfection of SARS-CoV-2, ferrets with different levels of NAb titres after primary SARS-CoV-2 infection were subjected to reinfection with a heterologous SARS-CoV-2 strain. All heterologous SARS-CoV-2 reinfected ferrets showed active virus replication in the upper respiratory and gastro-intestinal tracts. However, the high NAb titre group showed attenuated viral replication and rapid viral clearance. In addition, direct-contact transmission was observed only from reinfected ferrets with low NAb titres (<20), and not from other groups. Further, lung histopathology demonstrated the presence of limited inflammatory regions in the high NAb titre groups compared with control and low NAb groups. This study demonstrates a close correlation between a low NAb titre and SARS-CoV-2 reinfection in a recovered ferret reinfection model.
已在多个国家报告了实验室确诊的 SARS-CoV-2 再感染病例。此外，SARS-CoV-2 感染诱导的自然免疫力水平尚不完全清楚，也不清楚初次感染是否对再感染具有保护作用。为了研究血清抗体滴度与 SARS-CoV-2 再感染之间的潜在关联，用不同水平的中和抗体滴度的雪貂进行了异源 SARS-CoV-2 株的再感染。所有异源 SARS-CoV-2 再感染雪貂在上呼吸道和胃肠道中均表现出活跃的病毒复制。然而，高中和抗体滴度组表现出病毒复制减弱和快速病毒清除。此外，仅从中和抗体滴度较低（<20）的再感染雪貂中观察到直接接触传播，而其他组则没有。此外，肺组织病理学显示，与对照组和低中和抗体滴度组相比，高中和抗体滴度组的炎症区域有限。这项研究在康复雪貂再感染模型中证明了低中和抗体滴度与 SARS-CoV-2 再感染之间的密切相关性。
