Neocoronavirus and neocoronavirus are two different things. Most of the neocoronavirus vaccines are made by utilizing the neocoronavirus itself or the gene fragments, and there are three main types of adenovirus vector vaccines, inactivated vaccines, and recombinant protein vaccines available in the market at present. 1. Adenovirus vector vaccine is the one-shot vaccine. The adenovirus can carry the nucleic acid fragments of the neocoronavirus and deliver them efficiently to the cells to express the antigen, and a single vaccination can induce an immune protective response. 2. The one that requires two shots is the familiar traditional inactivated vaccine, which inactivates the live virus and then inoculates the human body as an antigen, and the composition of the vaccine is the closest to the natural viral structure. 3. The one that requires three shots is the recombinant protein vaccine, which is a vaccine made by genetically engineering the most effective antigenic components. The new mRNA vaccines now available can produce target proteins or immunogens that activate the body’s immune response against various pathogens. mRNA vaccines utilize the genetic sequence of the virus rather than the virus itself, so mRNA vaccines have no viral components and no risk of infection.