appear to be unusually efficient vectors of a variety of disease- 

 causing organisms. In their innnature stages, they often feed on 

 birds, rodents, and hares that are important reservoirs of patho- 

 gens, especially viruses and rickettsiae. 



Few ticks have been incriminated as reservoirs and vectors of 

 pathogenic viruses, but several species of hyalommas are known to 

 be hosts and vectors of the viruses causing several distinctive 

 acute infectious hemorrhagic fevers of human beings in the Soviet 

 Union, Unpublished studies by Baubney (conversation) indicate 

 that one of these same species may transmit in nature the virus 

 causing a Near Eastern encepheilomyelitis of equines. These same 

 tick species occur in North Africa and northern Sudan. Other 

 species cause paralysis of man and animals, apparently as a result 

 of toxins injected into the host while the tick is feeding. The 

 association of Hyalomma ticks with a niomber of other human and 

 veterinary diseeises is noted in the following text. 



Many Hyaloimna species, in our experience, attach readily to 

 man and feed on him. The "cursorial ticks" of North African and 

 Arabian deserts, as first described by Mann (1915 )> are several 

 species of hyalommas that come rushing from beneath every shrub 

 when persons or animals stop nearby. These are almost invariably 

 unfed adults, of uniform size, shape, color and genersLL appearance, 

 that have molted from the nymphal stage in rodent burrows beneath 

 shrubs. Although few of these highly agitated young adults actuals 

 ly attach to man, some do. 



Confusion in nomenclature has limited the value of many ear- 

 lier studies on biology and diseaseu. transmission in this group, 

 for it is often impossible to be certain which species the writer 

 used in his work. Considerable stvidy on this genus has been and 

 is being done in Russia, and it is frequently difficult for re- 

 viewers to determine exactly the species being reported and to 

 satisfactorily evaluate the reports. 



In addition, it should be indicated that the range of Hyalomma 

 ticks covers, in large part, a vastly undeveloped peirt of the world 

 in which little serious scientific research hsis been accomplished. 

 Before many years have elapsed, enough evidence probably will have 

 been presented to indicate that Hvalomma ticks are economically 

 among the most important of animBl ectoparasites to be found any- 

 where in the world. 



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