Effect of Trichinella spiralis infection on the experimental amebic liver abscess in hamsters.

The development of experimental amebic liver abscess in hamsters was inhibited by a previous infection with the nematode parasite Trichinella spiralis, such that liver abscesses were present in 26% of hamsters with T. spiralis infection and in 80% of T. spiralis-free controls. The protective effect of T. spiralis infection is believed to be exerted through a non-specific activation of cellular immunity, with macrophages as probable effector cells.