MICROBIAL DISEASES OF MAN AND ANIMALS. 



687 



Ten days intervene between the bite of the infecting tick and the first 

 sign of the infection. The temperature rises, it may be, to 106, or more, 

 and it remains high for a week. The animal is evidently very ill, it has 

 no appetite, and it rapidly loses strength and weight. Many red cells 

 are destroyed and anaemia may be marked. The urine is albuminous 

 and it is red because of the haemoglobin which it contains. Death may 

 occur in very acute cases as early as the second day. Animals which 

 recover from a severe attack are usually immune to the disease. The 



B 



D 



G 



H 



K 



FIG. 128. Babesia bigemina. Various stages of development in red blood cells. 

 A, young parasite; B, a twin-form; C-E, a multiple division; F-K, large pear-shaped 

 forms. (After Doflein.} 



immunity is not an absolute one, however, for blood taken from such 

 recovered animals is often infective; the parasite probably exists in them 

 in a latent form. 



There is no specific treatment for babesiosis. Some of the aniline 

 drugs, used in the treatment of trypanosomiasis, such as trypan-blue, 

 are of some value. 



Many districts are kept free from red water by not allowing cattle 

 coming from infected districts to enter them. Where it exists, the disease 

 is controlled by destroying the ticks on cattle with poisonous washes and 

 by occasionally plowing, or burning over, the pastures in order to destroy 



