What are inactivated vaccine, attenuated live vaccine and genetically engineered vaccine?

Also known as dead vaccine, it is an immunogen made by artificial mass culture and physical and chemical methods. Usually, multiple vaccinations are needed, and the immune effect has certain limitations. Dead vaccines mainly induce the production of specific antibodies, that is, basically only humoral immunity is produced.

Second, attenuated vaccine.

Is prepare from attenuated or nontoxic active pathogenic microorganism. Generally, humoral immunity and cellular immunity can be induced only once.

Third, genetically engineered vaccines.

Recombinant antigen vaccine, recombinant vector vaccine, DNA transgenic plant vaccine, transgenic vaccine. DNA recombination technology extracts antigen-related genes, and then expresses some protein or direct DNA fragments. After treatment, it is injected into the human body, causing some immune reactions and producing antibodies or memory cells against this antigen to achieve immune effect.