DISEASE RELATIONS 



MAN *; A. ponposum is said to attack African children's heads 

 and causes sToxaghing of the skin. This has not been substantiated, 



CATTLE ; Inflammation and sloiighing of mammae. Heartwater 

 (Rickettsia ruminantium ) . 



HORSES; Pyolymphangitis. 



REMARKS 



According to Robinson (1912*), A. pomposum (s A. variegatum 

 nocens ) occurs in the Rhodesias and T?ozambique chieTly in biishveld 

 from 2000 to 3000 feet elevation and seldom above 4-000 feet. He 

 further stated that this tick is notorious for the damage it does 

 to stock in the Rhodesias, where it is known as the "Pyaemia tick?*. 

 However, Morris (1933,1935,1936) attributed *tick- pyaemia'" in 

 Northern Rhodesia to A. variegatum . In Southern Rhodesia, Jack 

 (1918) referred *ixodTc lymphangitis'* to A. variegatum , Sinclair 

 (1916) associated skin diseases of cattle^with A. variegatum , 

 and Jack (1928,1937,1942) also mentioned only aT variegatum with 

 reference to abscesses and sloughing of the hosts' skin. In his 

 first two papers Jack did not differentiate between A. variegatum 

 and A. poi^osum, but in his 1942 report he stated that the local 

 highlanas where A. pomposum would be expected to occtir, are free 

 of amblyommas but tnat some male specimens of A. variegatum from 

 the lowlands may show a tendency to resemble A. pomposum . See 

 also IDENTIFICATION below. 



Theiler (correspondence) calls attention to the following 

 facts that may modify many of the above reports concerning A, 

 pomposum . Robinson's (1912,1926) remarks concerning A. pomposum 

 in Mozambique anS Southern Rhodesia are based on statements of 

 Ifr. E. M. Jarvis. Jack's records for Southern Rhodesia apparent- 

 ly are quoted from the same source, for no further data are pre- 

 sented. The extensive Onderstepoort collection has no speci- 

 mens from Southern Rhodesia. Theiler's correspondence with 

 Dr. Lawrence, Assistsint Director (Research) of the Southern Rhode- 

 sia Veterinary Department, indicates that he is not aware that A. 



*This record should be read in conjunction with statements in 

 RH4ARKS and in IDENTIFIGATIGN below. 



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