Transmission of Mammalian Piroplasm by an Argasid Tick

IT is the accepted view that parasites belonging to the suborder Piroplasmidae Wenyon, 1926, are exclusively transmitted by “hard” ticks belonging to the family Ixodidae Murray 1,2 . Most piroplasms of domestic animals have more than one Ixodid vector. In the laboratory, small mammal piroplasms belonging to the genera Babesia Starcovici, 1893, and Nuttallia Franca, 1910, are used as models for the diseases caused by piroplasms of domestic animals. This research, however, suffers from the drawback that the parasites cannot be biologically transmitted, except in two cases. Thus, Babesia rodhaini Van den Berghe, Vincke, Chardome and Van den Bulcke, 1950, a rodent piroplasm very commonly used in laboratory investigations, has no known vector; nor has Babesia hylomysci Bafort, Tirnperman and Molineux, 1970. The two small mammal piroplasms of which the vectors are known are Nuttallia microti Coles, 1914, and Nuttallia danii Tsur, Hadani and Pipano, 1960 (and the probably identical N. tadzhikistanica (Krylov and Zanina, 1963), Krylov, 1964). The vectors of these piroplasms are Ixodes trianguliceps 3 Birula, 1895, for the former, and three species of Hyalomma and two species of Rhipicephalus 4 for the latter. All of these vectors belong to the Ixodidae.