There are currently five variant strains of neocoronavirus, which are Alpha, Beta, Gamma, Delta and Omicron. According to the 9th edition of China’s new coronavirus pneumonia diagnosis and treatment protocol, the current variant strains of concern (VOC) considered by the World Health Organization (WHO) are the Alpha, Beta, Gamma, Delta and Omicron strains. 1. Alpha mutant: Slightly more virulent and infectious than the original strain. This strain has a deletion of a type of spiking protein, which may lead to missed detection because the target site at the deletion site cannot be detected. 2. Beta mutant: Increased virulence and infectivity. 3. Gamma mutant: Three mutations have occurred in this mutant strain, making it more transmissible. 4. Delta mutant: This strain is more infectious and virulent than the above mutants. People infected with this strain are more likely to become seriously ill. 5. Omicron: This strain has now replaced the Delta strain as the predominant strain. This strain is more transmissible than the Delta variant, but is less pathogenic. Tip: In this article, “new coronavirus pneumonia” and “new coronavirus pneumonia” were renamed to “new coronavirus infection” on December 26, 2022, as announced by the National Health Commission.