ii2 MILK AND THE PUBLIC HEALTH CHAP. 



with the condition, he frequently speaks of it as spurious cow- 

 pox, and attaches no significance to its occurrence. In the 

 considerable number of cases which the writer has come across 

 the cowkeeper has always milked the cows as usual and added 

 the milk to the rest for sale. 



The relationship of ulcerated teats to human disease is 

 at present undecided. Systematic bacteriological investiga- 

 tions of sore teat conditions do not seem to have been 

 made. 



That teat ulcers may be secondarily infected has been demon- 

 strated in the case of diphtheria, and two outbreaks may be 

 briefly mentioned. Dean and Todd 1 in 1902 described a 

 small outbreak in which undoubted diphtheria bacilli were 

 isolated from the teat lesions and from the milk. In this 

 outbreak certain individuals suffered from diphtheria and 

 others from sore throat, probably diphtheritic. They obtained 

 their milk supply from two cows. The cows were affected 

 with papules and ulcers on the udders and teats, which com- 

 menced about ten days before the outbreak. One of the cows 

 also showed mastitis in one quarter, the fluid secreted being 

 scanty, ropy, and semi-purulent in appearance. True diph- 

 theria bacilli which were virulent were isolated both from the 

 lesions and from the milk. A healthy cow milked immediately 

 after the diseased cows and by the same milker developed 

 vesicles upon the teats, but neither in the vesicles nor in the 

 ulcerative stage of the disease could diphtheria bacilli be 

 demonstrated. The investigators also showed that in calves 

 infected with the eruptive disease no diphtheria bacilli could 

 be demonstrated, while injecting a calf with 10,000 units of 

 diphtheria antitoxin did not prevent the vesicular eruption. 

 The authors came to the conclusion that the lesions in the 

 cow were not due to the diphtheria bacillus, but that the latter 

 was a superadded infection. 



Ashby, 2 in 1906, described an extensive outbreak of diph- 

 theria, affecting seventy-five persons living in forty-three houses: 

 Forty-two of these houses were supplied by two milkmen. Of 

 the cows of one dairyman (Z.) all the teats of two cows were 

 badly ulcerated, and the teats of three other cows were affected 



1 Journal of Hygiene, 1902, ii. p. 194. 

 a Public Health, 1906, xix. p. 145. 



