世界卫生组织(World Health Organization, WHO)于2021年11月26日将首次在南非报告的新型冠状病毒 B．1.1.529 变异株列为受关注变种(variant of concern, VOC)，并将其命名为奥密克戎(Omicron)。该变异株存在约50个突变，仅在刺突蛋白区域就有至少30个突变，远远超过其他流行株的突变位点数量。根据对突变位点的分析以及初步实验证实，该毒株可能具有极强的传染性以及免疫逃逸能力。Omicron变异株会怎样影响新冠疫情的走向引起了各国的广泛关注，本文将从Omicron变异株的基本特征、检测、致病性、传染性、免疫逃逸等方面进行综述。

On November 26, 2021, World Health Organization (WHO) designated the B．1.1.529 variant firstly reported in South Africa as a variant of concern (VOC) of SARS-CoV-2, named Omicron. There are about 50 mutations in this variant, and at least 30 mutations in the spike protein region alone, which far exceeds the number of mutation sites in other endemic strains. The analysis on mutated sites and preliminary experiments confirmed that the variant may be highly contagious and associated with immune escape. How Omicron variant will affect the pandemic has aroused wide public concern in various countries. This review focused on the basic characteristics, detection, pathogenicity, infectivity, and immune escape of Omicron variant.