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Canine leishmaniasis is a vector-borne disease caused by protozoa of the genus Leishmania that affect dogs, humans and wildlife. Sandflies of the genera Phlebotomus and Lutzomyia are the primary vectors. Canine leishmaniasis is an exotic and controlled disease in South Africa. The main purpose of our risk assessment study was to evaluate the likelihood that this exotic disease could enter and be established in South Africa through importation of live dogs. Risk analysis to the spread of the disease follows the World Organization for Animal Health (OIE) formal method of quantitative risk assessment documented as a step-by-step process. We have identified and discussed 11 possible risk factors involved in three steps for final assessment. The annual average number of diagnostic tests performed on imported dogs from 44 countries for 2011-2015 was 1158. Leishmania is reported to occur in 21/44 (47.7%) exporting countries. A total of 71.1% of Leishmania positive dogs were imported from these endemic countries. The yearly percentage of Leishmania positive dogs ranged from 0.2% to 2%. Three confirmed clinical and fatal cases of leishmaniasis in dogs of unidentified origin have been reported by our laboratory and the state veterinarians. The disease has been reported in neighbouring countries as well as the putative sandfly vectors. This study concluded that the risk for the introduction and degree of uncertainty of Leishmania in imported dogs in South Africa are moderate. Risk mitigation and recommendations such as investigations into possible occurrence of autochthonous leishmaniasis in the country, surveillance in its wildlife reservoirs and systematic surveillance of sandfly populations are discussed.

Quantitative real-time PCR assays previously developed for the detection of Theileria equi and Babesia caballi, were combined in a single multiplex TaqMan qPCR platform for the simultaneous detection of both heamoprotozoan parasites in equids. The multiplex equine piroplasmosis (M-EP) qPCR assay was shown to be efficient and specific. The detection limit was determined to be 1.4 × 10 -4 % parasitized erythrocytes (PE) for T. equi and 2.8 × 10 -4 % PE for B. caballi. The effect of differential DNA concentrations on the outcome of the M-EP qPCR for each target species was also investigated. The data demonstrated that the assay could reliably detect both targets, over a range of at least 1000-fold difference in target concentrations, without loss of sensitivity. The assay was subsequently evaluated on 243 field samples collected from areas where limited tick control strategies were implemented. The IFAT detected circulating T. equi and B. caballi antibodies in 100% and 92% of the samples, respectively. The M-EP qPCR assay detected T. equi parasite DNA in 98% of the samples, while B. caballi could only be detected in 6% of the samples tested, confirming that B. caballi infections generally occur at extremely low parasitaemias that rarely exceed 1%. The developed M-EP qPCR assay therefore serves as a reliable tool for the rapid diagnosis and epidemiological survey of equine piroplasmosis., (Copyright © 2018 Elsevier B.V. All rights reserved.)