ABSTRACT
The variant of the original SARS-CoV-2, originated in China, spread throughout the world, and has been undergoing constant mutations, leading to an increase in its variants. In order to understand SARS-CoV-2 variants properly, it is important to have a brief idea about the replication and life cycle of the original SARS-CoV-2 virus. The United States SIG, assigned a classification system for variants, according to this, SARS-CoV-2 variants are grouped into three categories, variants of interest, variants of concern, and variants of high consequences. Increased viral transmissibility, increased disease severity, reduced antibody generation and efficiency, and reduced response to treatment and disease management are grouped under this category. Researchers have reported evidence for reduced vaccine-induced protection from severe disease along with reduced production of effective neutralizing antibodies in response to natural infection. The human system has memory T-cells and antibody-secreting plasma cells.
