Parasite persistence in the aetiology of Chagas disease

Abstract

Two primary hypotheses are proposed to account for pathogenesis in chronic Trypanosoma cruzi infections: that the persistence of T. cruzi at specific sites in the infected host results in chronic inflammatory reactivity and that T. cruzi infection induces immune responses which are targetted at self tissues. The data supporting parasite persistence as the primary cause of disease in T. cruzi infection have been recently reviewed and the reader is referred to this review for extensive documentation of most of the arguments outlined herein. This manuscript will briefly reiterate the main points of this previous review, adding additional data that have been presented since its publication. Then, philosophical and practical arguments on why Chagas disease should be investigated and treated as a parasitic infection and not as an autoimmune disease are presented. This is admittedly an 'opinion piece' and not a balanced review of the literature on Chagas disease. There are substantial data other than those reviewed here, which have been presented in support of the autoimmunity hypothesis. It is left to others to review that body of literature.