Deliberate stimulation of the host’s immune response. Active immunization involves administration of antigens or immunologic adjuvants. Passive immunization involves administration of immune sera or lymphocytes or their extracts (e.g., transfer factor, immune RNA) or transplantation of immunocompetent cell producing tissue (thymus or bone marrow).
A procedure in which a dead or inactive bacteria, virus, or toxin is given orally or by injection to trigger an immune response to that specific disease.
A process that prepares the body to fight and prevent an infection through the injection of material from the infecting organism, or by using an attenuated (non- disease-causing) strain of the organism itself.
Naturally or artificially induced resistance to disease.
The process of inducing immunity, or internal resistance to disease, in a person of any age but especially in children, who are very vulnerable to diseases after the first year as the natural immunity they received from their mothers wears off. Immunization can be induced in two main ways. The first, and most familiar, is active immunization, in which a vaccine is introduced into a person’s system, either by injection or by mouth, triggering the formation of antibodies and the development of immunity for a limited time or a lifetime, depending on the vaccine. In the less common passive immunization, antibodies are directly injected into a person’s body, supplying a short-term immunity. This approach is sometimes used during pregnancy when a woman has been exposed to a dangerous disease or has Rh incompatibility.
Process (e.g., vaccination) by which resistance to an infectious disease is induced or increased.
A preventative measure to boost immunity of susceptible individuals by administering killed organisms or inactivated toxins.
The process of inducing the immune system to produce protective antibodies to create immunity as a preventive measure against particular infectious diseases. Active immunization is accomplished when a person receives a vaccination that introduces antigens into the body that prompt the body’s immune system to create antibodies directed against the antigen (see antigen). The antibodies are generally administered as a vaccine that consists of a suspension of whole or partial bacteria or viruses that have been inactivated or treated to prevent them from causing disease in the person being immunized. Passive immunization occurs when an individual is given antibodies to provide immediate protection against an antigen or an infective organism such as bacteria. Immunizations given routinely in the United States include vaccines against measles, mumps, and rubella; against tetanus, diphtheria, and pertussis, called the DTaP vaccine; against hemophilus influenza B (hib); against chickenpox with varicella vaccine; against hepatitis B for those at risk of exposure; against influenza A, for those at high risk of serious consequences from flu.
The production of immunity by artificial means. Passive immunity, which is temporary, may be conferred by the injection of an antiserum, but the production of active immunity calls for the use of treated antigens, to stimulate the body to produce its own antibodies: this is the procedure of vaccination. The material used for immunization (the vaccine) may consist of live bacteria or viruses so treated that they are harmless while remaining antigenic or completely dead organisms or their products (e.g. toxins) chemically or physically altered to produce the same effect.