Question

What are the first , second and third order generation of vaccines refer to? give examples

Answer 1

FIRST GENERATION vaccines are live,attenuated vaccines made from whole organism .They can become threat if injected in immunocompromissed patient by inducing killer T cells.ex.POLIO VACCINE ,SMALL POX
SECOND GENERATION vaccines are sub-unit vaccines prepared by genetic engineering which includes protein antigens or recombinant proteins. They can not include killer T cells.ex HEPATITIS B,HERPES VIRUS .
THIRD GENERATION vaccines made from DNA.DNA of pathogen is inserted in the body which replicates forming many copies of DNA which codes for specific proteins  which are antigens for host.Immune system develops antibodies against it.ex Ebola vaccine

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