Control and eventual eradication of Trypanosoma evansi infection in dromedary camels after an episodic outbreak in mainland Spain: An example in a non-endemic area

In 2008, Trypanosoma evansi was detected on a camel farm in mainland Spain. The animals were isolated, confined in a closed stable, and treated twice with melarsamine (Cymelarsan®, Merial, Lyon, France) with an interval of 1 month. Clinical and laboratory examinations by means of parasitological, serological, and molecular procedures (polymerase chain reaction (PCR)) were carried out regularly for 6 years. After the treatment, all parasitemic camels were cleared of parasites, and in the seropositive camels a progressive decrease in antibody levels was observed, with complete disappearance of antibodies between 15 and 21 months, except in one animal which showed doubtful Ag-Ab reaction at 21 months post treatment. In the next assessment, 6 months later, the diagnostic tests conducted on all animals had a negative result.The diagnostic and therapeutic tools recently developed against T. evansi will evidence new and alternative approaches after the parasite is detected, particularly if outbreak occurs in geographically localized areas in territories free of the disease.