What is the action of making a person immune to infection called?

The action of making a person immune to infection is best described by the term "immunization." This process involves the administration of a vaccine or immunoglobulin to stimulate the immune system to protect against specific diseases. Immunization leads to the production of antibodies and the development of memory cells, allowing the body to recognize and fight off pathogens in the future.

While vaccination is a related term and often used interchangeably with immunization, it specifically refers to the act of administering a vaccine. Immunization encompasses a broader range of methods, including vaccination, that ultimately result in increased immunity. Inoculation traditionally refers to introducing a vaccine into the body but is often used in historical contexts. Exposure simply means coming into contact with a pathogen, which does not guarantee immunity. Therefore, immunization provides the most comprehensive understanding of achieving immunity against infections.