In immunology, seroconversion is the development of specific antibodies in the blood serum as a result of infection or immunization. After seroconversion has occurred, the antibodies can be detected in blood tests for the disease. During an infection or immunization, antigens enter the blood, and the immune system begins to produce antibodies in response. Before seroconversion, the antigen itself may or may not be detectable, but the antibody is, by definition, absent. During seroconversion, the antibody is present but not yet detectable.
