OBJECTIVE: To report 45 cases of melioidosis in dogs and cats from northern Australia and analyse trends in epidemiology, clinical presentation, pathogenesis and response to treatment over a 27-year period.
DESIGN: Retrospective and prospective analysis of clinical records.
RESULTS: Forty-five cases were diagnosed (24 dogs, 21 cats) from the Northern Territory and Queensland over 27 years, with most diagnosed during the wet season (December-March). Presentations most commonly involved localised infection (wounds, cellulitis or abscessation) or primary neurological disease. Other presentations included septic arthritis, urinary tract infection, pneumonia/pyothorax, disseminated disease, ocular infection and reproductive tract infection. Dogs more often had disease of the skin and subcutis, whereas cats showed more variable clinical manifestations. Predisposing causes such as immunosuppression were not identified in most cases. Treatment and outcome data were available for 15 cases: 5/11 (45%) cats and 4/4 (100%) dogs recovered; one cat was lost to follow-up (LTFU); one cat was receiving treatment at the time of manuscript submission and 4/11 (36%) cats were euthanised. Of 13 animals that died or were euthanised due to melioidosis, seven presented with neurological disease.
CONCLUSION: Melioidosis is a serious, potentially fatal infection in dogs and cats in tropical and occasionally subtropical regions of Australia. Diverse clinical presentations may delay definitive diagnosis and initiation of appropriate therapy. Timely diagnosis and prompt administration of appropriate antimicrobials were critical to achieve control and reduce relapse and mortality.