Immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is central to long-term control of the current pandemic. Despite our rapidly advancing knowledge of immune memory to SARS-CoV-2, understanding how these responses translate into protection against reinfection at both the individual and population levels remains a major challenge. An ideal outcome following infection or after vaccination would be a highly protective and durable immunity that allows for the establishment of high levels of population immunity. However, current studies suggest a decay of neutralizing antibody responses in convalescent patients, and documented cases of SARS-CoV-2 reinfection are increasing. Understanding the dynamics of memory responses to SARS-CoV-2 and the mechanisms of immune control are crucial for the rational design and deployment of vaccines and for understanding the possible future trajectories of the pandemic. Here, we summarize our current understanding of immune responses to and immune control of SARS-CoV-2 and the implications for prevention of reinfection.

对严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 感染的免疫力对于长期控制当前疫情大流行至关重要。尽管我们对 SARS-CoV-2 免疫记忆的了解迅速推进，但了解这些反应如何转化为个人和群体层面的再感染保护仍然是一项重大挑战。感染后或疫苗接种后的理想结果是高度保护性和持久的免疫力，从而建立高水平的群体免疫力。然而，目前的研究表明，恢复期患者的中和抗体反应减弱，并且记录在案的 SARS-CoV-2 再次感染病例正在增加。了解对 SARS-CoV-2 的记忆反应动态和免疫控制机制对于合理设计和部署疫苗以及了解大流行未来可能的发展轨迹至关重要。在此，我们总结了目前对 SARS-CoV-2 免疫反应和免疫控制的理解以及对预防再感染的影响。