Children may become infected with many bacteria or viruses, which can cause illness. Some of these organisms may also produce toxins, which can result in serious damage. Following most infections the body develops protection (resistance) against further infections by the same organism or against the toxins which these organisms produce. The body is now said to be immune to (protected against) that specific organism or toxin. This protection is called immunity. The body produces immunoglobulins (antibodies) and white cells to provide immunity (protection). Immunity can follow a natural infection or be induced by immunisation.
Immunity is the protection which the body develops against further damage by an organism or toxin.