What type of immunity is established in a child diagnosed with rubeola?

The correct answer is active immunity. A child diagnosed with rubeola, commonly known as measles, develops an immune response to the virus once exposed. In active immunity, the individual's own immune system recognizes and responds to pathogens, producing specific antibodies against them. This type of immunity can be acquired through natural infection, as is the case with rubeola, where the child encounters the virus and mounts an immune response.

Passive immunity, in contrast, is the transfer of pre-formed antibodies from one individual to another and does not result in the formation of long-lasting immunity, which would not apply here as the child’s immune system is actively working against the rubeola virus.

Natural immunity encompasses immunity that is gained through natural exposure to pathogens, which overlaps with active immunity in this scenario since the child is actively developing an immune response to the viral infection.

Innate immunity refers to the non-specific defense mechanisms that one is born with, such as physical barriers and immune cells that act immediately upon infection, but it does not involve the adaptive processes typical of a specific response to infectious agents like rubeola.