Hyperimmunization is the presence of a larger than normal number of antibodies to a specific antigen. This creates a state of immunity that is greater than normal. Immune system overactivity can cause many different diseases.
Craft J. The adaptive immune system. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 46.