Tyvelose is an unusual 3,6-dideoxyhexose terminal sugar and the immunodominant component of glycoprotein antigens in the parasitic helminth T. spiralis, which is responsible for trichinosis in humans. It is produced in high amounts by the infective larva and is immunodominant during the muscle stage of infection. Mice immunized with tyvelose-BSA produce IgG1 antibodies to tyvelose but are not resistant to infection by T. spiralis. Tyvelose-specific antibodies (2.5 mg/20 g) administered to rat pups leads to expulsion of first stage larvae from the intestine within one hour.