In order to protect susceptible people which immunization agent is most effective

Live attenuated vaccine or live bacterial vaccine

Protection of susceptible people, usually used vaccination measures are: ① Artificial passive immunization, that is, containing specific antibodies to human or animal serum as an immune preparation, injected into susceptible people to prevent infection. Commonly used preparations are human blood or placental blood made of gammaglobulin, specific high-value immunity gammaglobulin and antitoxin (animal serum) and so on. Passive immunization is effective after injection, but the duration is only 2 to 4 weeks, generally should be used in the incubation period after exposure to early, can have complete or partial protection, usually used for measles or hepatitis A. Antitoxins (e.g., tetanus, diphtheria antitoxin, etc.) are only used for prophylaxis in emergency situations, and skin tests should be done before use. Passive immunization is an emergency measure, and the sooner it is used after exposure, the better. But the incubation period of infectious diseases is long due to passive immunization agents effective time is short, premature application may not necessarily achieve the purpose of prevention. ② active immunization, that is, inoculation of biological products (vaccines) so that the body produces specific immunity, 1 to 4 weeks after the injection began to appear, lasting from a few days to a few years. Commonly used preparations are: live attenuated bacteria (epidemic) vaccine, is the choice of strong immunogenicity, but non-toxic or toxicity of live strains or live strains of venom made by human blood culture, such as BCG, cowpox vaccine, measles vaccine, polio vaccine and so on. This kind of vaccine inoculation quantity is small, the number of times of vaccination is small, the immunization effect is good and long-lasting. Inactivated bacterial (epidemic) vaccine is the selection of immunogenic bacteria or virus cultures, made after inactivation, such as pertussis vaccine, cerebral hemorrhagic bacterial vaccine, rabies vaccine and so on. This vaccine is weak antigenicity, vaccination volume, need to be vaccinated many times, poor immune effect, short immune period, in addition to the bacterial exotoxin by formaldehyde treatment, become non-toxic and retain its antigenicity of the preparation, known as toxin-like toxins, such as diphtheria toxoid. Tetanus toxoid, also has immunoprophylaxis.