Secondly, thestudy assumed the occurrence of CNS involvement by relapse of parasitaemia afterhaemolymphatic clearance with diminazene aceturate, as has been done in previous studies.However, assessment of plasma concentrations of acute-phase protein, C-reactive proteinand haptoglobin could also be used as a marker for experimental infections.16,33 Thirdly, it is difficult to interpret brain pathology in terms ofrelapse following treatment with trypanocidals, as they, too, have been shown to inducebrain pathology. This evidence concerns the gene HP and infection.