What is passive immunization primarily used for?

Passive immunization is primarily utilized to provide immediate protection against infections. This approach involves the administration of pre-formed antibodies to an individual, which offers quick immunity without requiring the body to generate an immune response. This form of immunization is particularly useful in situations where immediate protection is needed, such as post-exposure prophylaxis for certain infections or during outbreaks where an individual may be at high risk.

For instance, in cases of rabies exposure or when dealing with patients who have compromised immune systems, passive immunization can help swiftly equip the body with the necessary antibodies to combat the pathogen effectively. In contrast, the other options concern different aspects of immune function: enhancing immune response generally refers to active immunization, where the body is stimulated to produce its own antibodies over time; training the immune system speaks to methods that educate the immune cells for future defense; and eliminating existing pathogens relates more to therapeutic interventions rather than immunization strategies.