Effect of experimentally induced trichinellosis on the infection with Erysipelothrix rhusiopathiae in rats.

Infection with Erysipelothrix rhusiopathiae in rats infested 20 days earlier with Trichinella spiralis developed more slowly, the clinical and pathoanatomic changes in the joints were expressed to a less extend, and the mortality rate was lower. The erythrocyte sedimentation rate, the precipitin formation and the phagocytic activity of the macrophages did not considerably change. Experiments carried out to elucidate this fact did not reveal any antigenic or antagonistic relationships between parasite and bacterium nor any protective effect of the host's serum. The inhibitory influence of corticosteroids on the defence forces was not completely manifested in the rats infested. This fact might be explained by interrelations depending both on the cycle of helminth development and on the non-specific immunological reactivity of the organism, the latter being stimulated by the helminth invasion.