The California Immunization Registry (CAIR) is a secure, confidential, web-based database that stores the immunization records of children and adults. Immunization registries help medical practices and other health care providers keep patients of all ages up-to-date on vaccinations by avoiding under-immunization or over-immunization and assists health care providers and health departments by collecting data on the immunization status of the community. All 50 states have immunization registries.