Active immunity is defined as immunity to a pathogen that occurs following exposure to all or part of that pathogen. When the body is exposed to a novel disease agent, a cascade of signaling molecules ...

Active immunity provides "resistance to reinfection from a pathogen, or a 'bad bug,'" says Dr. Charles C. Bailey, director of infection prevention at St. Joseph Hospital and Mission Hospital in ...

Adaptive immunity, also known as acquired immunity, is the third line of defense and, whilst slower to act, protects an organism from specific pathogens. Adaptive immunity can be further classified ...