However, people inject inactivated virus (in general); Inject animals with attenuated virus.

Injection of serum (antibody) belongs to passive immunity-generally used for first aid or very dangerous injury. For example, when bitten by a rabid dog or a poisonous snake. Not often used.

Injecting antigen is active immunization. Inactivated vaccines are generally used for immunization of very dangerous diseases, and attenuated vaccines are used for diseases with less risk or diseases with weak immune response.

The effect is different. Generally, the effective period of antigen injection is relatively long, which belongs to self-memory cell immunity; However, the effective period of antibody injection is short, which will be consumed gradually with metabolism and will not produce new antibodies.