Immunological assays are available for measuring the humoral immune response after parasitic infections. For the detection and quantitation of antibodies or antigens an immunoassay has to fulfill three basic requirements: highly specific, highly sensitive, and reproducible. The field of application and the quality of antigen/antibody available are the main variables which determine the choice for one specific assay. A test system may be adequate for population screening or for individual diagnosis. Ideally, it is a single definitive test which can equally detect antibodies in low-responders, in people with recently contracted infection or with high titers and clinical signs, and be suitable for a posttreatment follow-up.
The stability of the antigen-antibody complex (avidity) determines the success of all immunological assays.
IFA, EIA, WB
The indirect immunofluorescence (fluorescent antibody) assay (test) (IIFA, IFA, IIFAT, IFT) has long been the best choice in...