Efficacy of rifampicin in the treatment of experimental acute canine monocytic ehrlichiosis

Results: By day 21 post-inoculation, all infected dogs became clinically ill and thrombocytopenic, seroconverted and were PCR positive in at least one tissue. Clinical scores and antibody titres did not differ between the treated and infected untreated dogs throughout the study. The rifampicin-treated dogs experienced an earlier resolution of their thrombocytopenia (Kaplan‐Meier survival plot, P ¼0.048), and the median platelet counts were significantly higher in the treated compared with the infected untreated dogs on post-inoculation days 42 (P ¼0.0233) and 98 (P ¼0.0195). At the end of the study, three treated and six untreated infected dogs remained PCR positive in one tissue each. Conclusions: The rifampicin treatment regimen applied in this study hastened haematological recovery, but was inconsistent in eliminating the acute E. canis infection.