PREVENTIVE MEDICINE 359 



out the summer and autumn to December, when there invariably 

 appears a sudden and pronounced increase. A. Gofton compiled a 

 table from the official returns which shows very clearly the rise and 

 fall of this disease, and he says that this is identical with that which 

 he observed in the army under active service conditions.* No 

 satisfactory explanation of this seasonal fluctuation has as yet been 

 offered. 



SARCOPTIC MANGE. 



Varieties of Sarcoptes scabei affect man, horse, ox, sheep, dog, 

 pig, goat, camel and other animals. Each species of animal has 

 its own variety, but the parasite may occasionally pass from one 

 species of host to another, although under such conditions, as a rule, 

 the infection is only of limited duration. Thus bovine sarcoptic 

 mange frequently affects milkers, causing " dairyman's itch " a 

 condition well known to veterinary surgeons. Equine sarcoptic 

 mange occasionally passes to grooms and hospital attendants. 

 Canine sarcoptic mange is frequently met with, at least by veteri- 

 nary practitioners, located on people ; the author has seen a man, his 

 wife and child all badly affected with sarcoptic mange contracted 

 from a Yorkshire terrier. 



In horses sarcoptic mange is often considered the most difficult 

 to cure, owing to the burrowing habits of the female, but the 

 psoroptic variety is frequently equally refractory. It is doubtful 

 if a period less than two months could be allowed with safety for 

 treatment and isolation. 



Sarcoptic Mange of the Ox. From time to time cases of 

 sarcoptic mange are reported in the veterinary journals as if this 

 parasite was a rare one on bovines. As a matter of fact it is very 

 common, far too common, among the dairy cows of cities. Fillers 

 also has found it of common occurrence in the winter time. This 

 disease is not scheduled, though many think that it should be. With 

 this we concur, as the presence of mange in dairy cows is an indica- 

 tion of neglect, and clean milk cannot be obtained from mangy 

 cattle. Unlike the disease in horses bovine sarcoptic mange is 

 confined almost exclusively to the root of the tail and the posterior 

 region of the udder, rarely it spreads forward. A peculiarity of 

 bovine sarcoptic mange is the readiness with which the parasites 

 are obtained from a scraping ; in a very small area the author has 

 often found an enormous number of parasites in all stages of 



* Paper read before Conference of Veterinary Inspectors, Newcastle- 

 on-Tyne, llth August, 1919; Vet. Record, llth October, 1919. 



