b) Artificial Active Immunity:
In artificial active immunity, immunity is attained by the host in response to the antigen got by vaccination. Vaccines are preparations of live (attenuated) or killed microorganism or their products (toxoids).
vaccination
Live Vaccine (attenuated): in this preparation, live microorganisms are attenuated by different methods. Attenuation results in the loss of pathogenicity without the loss of antigenicity of the microorganisms.
E.g.: Anthrax vaccine,
BCG (Bacille Calmette Guerin),
Sabin Vaccine (oral Poliomyelities Vaccine),
Measels Vaccine.
Vaccines prepared with killed microorganisms: In this vaccines, microorganisms are killed in their virulent phase either by heat or antiseptics. While killing, care is taken not to denature the antigen by excessive heat or strong detergents.
E.g.: Salk vaccine,
Influenza vaccine, vaccine
TAB vaccine,
Pertussis vaccine,
Toxoid,
Tetanus Toxoid (TT),
Diptheria Toxoid,
Triple Vaccine (DPT).