When adenovirus carrier vaccine is given as a third dose, it is usually meant as a booster shot for the new Crown Vaccine immunization program, and there is no need to worry about any adverse effects. Adenovirus carrier vaccine can be given as a booster shot. The booster vaccination can be an adenovirus vector vaccine or a recombinant protein vaccine. After 2 doses of inactivated vaccine, a sequential booster can be given with the adenovirus carrier vaccine. The use of adenovirus vector vaccine as a booster shot has the advantages of effective neutralization of mutated strains and good safety, and it is beneficial for enhancing the immune response of human cells and preventing mutated types of viral infections. Therefore, there is no need to worry about or overdo the situation where the adenovirus-vectored vaccine is given as the third dose.