Trichinosis, the infection caused by the nematode Trichinella spiralis, is acquired by ingestion of raw or undercooked meats (primarily pork). Although the nematode may be found in a wide variety of animals worldwide, the domestic pig is the primary source of infection in developed nations.

Serology has also been an important tool in the diagnosis of trichinosis for several decades. Various methodologies; such as ELISA, latex agglutination (LA), indirect hemagglutination (IHA) and bentonite flocculation (BFT) have been used. Although various classes of antibodies have been detected, no single class has shown superior diagnostic ability over the others.

BFT has been the method of choice for serology but suffers from nonspecific reactions, some lack of sensitivity (measurable antibodies often do not appear until 3 to 4 weeks after infection) and difficulty in performing the test. Recently, an excretory-secretory (ES) antigen has been purified from the larvae of infected pigs. This antigen has a high degree of specificity for T. spiralis and has been used in several large scale studies.