Caused by Rickettsia rickettsia and transmitted by Dermacentor spp ticks, RMSF is found throughout the Americas. R. rickettsia replicates in vascular endothelium and can cause multi-systemic severe disease in both man and dogs. Clinical signs include:

Diagnosis is by haematology, direct immunofluorescence of infected tissue (store tissues in normal saline on ice), isolation of the organism at specialist laboratories, and serology.

Treatment is with oxytetracycline (22 mg/kg three times daily for up to weeks) or doxycycline (10 mg/kg twice daily for 1 week).

Back to menu