Follow-up survey of the prevalence, diagnosis, clinical manifestations and treatment of Spirocerca lupi in South Africa.

Spirocercosis is an important disease in South Africa. The object of this study was to determine if there had been a change in the prevalence, clinical manifestations and treatment of Spirocerca lupi over a 14-year period. A questionnaire was sent to 577 veterinary practices throughout South Africa in 2012. Of responders, 76% indicated that S. lupi occurred in their area, whilst 24% indicated that it did not; 84% considered S. lupi not to be a new phenomenon, whereas 16% considered it to be new. Monthly or seasonal distribution of the disease was not reported, and 76% of responders reported it to occur in no specific breed of dog, whereas 24% reported a breed risk, most considering large breeds to be at greater risk. No specific age or sex was identified as at higher risk. Common owner complaints were vomiting, weight loss, cough, or regurgitation. Reported clinical findings tended to mirror the clinical signs reported by owners. Most common diagnostic methods used were radiology, endoscopy, faecal flotation, and post mortem examination. Forty-four percent did not report seeing asymptomatic cases, 40% reported asymptomatic cases and 16% did not know. Associated complications were reported by 85% of responders, and included oesophageal neoplasia, hypertrophic osteopathy and acute haemothorax. Four different drugs were used as therapy: doramectin, ivermectin, milbemycin and Advocate®, with 9% of the responders using a combination of these four; 85% considered treatment to be effective and 15% ineffective. Treatment was considered more effective if the disease was diagnosed early and there were no complications. Two important conclusions were that more cases are being seen and that efficacy of therapy has increased, with a decrease in the mortality rate.