Without experimental testing, we do not know what effect the mutation has on the virus: whether it will lead to better outcomes (e.g., the mutation reduces the virus’s transmissibility), to worse (e.g., the mutation increases its virulence), or none (e.g., the mutation does not create any properties that “the mutated ” distinguished the virus from the original virus). Some variants of the coronavirus appear and disappear during the pandemic, other variants are more successful, persist and spread in the population. So far, several significant variants of the SARS-CoV-2 virus have been documented worldwide since the beginning of the COVID-19 pandemic.

From the very beginning of the pandemic, changes occur in the genome of the virus, in the sense of a higher ability to bind to the receptor, which leads to easier transmission, i.e. higher transmissibility. From December 2020, it is possible to observe the appearance of variants bearing clear features of so-called escape mutations, which allow the variant of the coronavirus to escape from the pressure of antibodies induced by the immune response after vaccination or after an illness. All essential mutations that give the virus an evolutionary advantage, i.e. easier transmission and escape from antibodies, arise in the world independently of each other, as a result of selection pressure.