What term describes immunity gained from recovering from an illness?

The term that describes immunity gained from recovering from an illness is naturally acquired active immunity. This type of immunity develops when an individual is exposed to a pathogen and their immune system responds by producing specific antibodies and memory cells. Once the infection is cleared, the immune system retains a memory of the pathogen, allowing for a more rapid and effective response if re-exposed to the same pathogen in the future.

Naturally acquired active immunity contrasts with passive immunity, which involves the transfer of antibodies from another individual, such as from mother to child through the placenta or breast milk. Innate immunity refers to the natural defenses present at birth, such as skin and mucous membranes, that provide immediate, but non-specific, protection against pathogens. Acquired immunity is a broader term that encompasses all forms of immunity gained through exposure, including both active and passive immunity, but it does not specify the source as naturally acquired.

The specificity of naturally acquired active immunity highlights its importance in providing long-lasting protection against diseases following infection, which can enhance a person's overall immune response to future encounters with the same pathogen.