252 VETERINARY HYGIENE 



of foreign origin or of contaminated fertilisers, are obviously 

 largely out of control, and such outbreaks must continue to occur 

 so long as foodstuffs are imported from countries where the disease 

 is of an epizootic nature. As the chief Veterinary Officer in his 

 report for 1913 says : " The incidence of anthrax in this country 

 depends largely upon factors which cannot be controlled by the 

 Anthrax Order. The Order is designed to control the spread of 

 anthrax once a case has occurred on premises and to prevent a 

 recurrence of the disease. That it is successful in these respects 

 is borne out by the fact that the disease recurs on the same premises 

 in only a small minority of cases, and the number of deaths per 

 outbreak is usually below two." 



When outbreaks do occur which fall within the second or pre- 

 ventable group, they are usually due to the cupidity of a dairyman 

 who cuts the throat of a sick cow in an attempt to salve the carcase 

 for human consumption; or the animal may have died and it is 

 skinned for the sake of its hide. 



In man the disease is contracted, as a rule, through inoculation 

 of cutaneous abrasions on the hands and arms when the carcase of 

 an animal that has died of anthrax is skinned, or when such an 

 animal is slaughtered and dressed. Cattlemen, butchers and 

 knackers are liable to infection under these conditions (malignant 

 pustule). Anthrax is also conveyed to people by handling infected 

 hides or their products. Infection may also occur by inhalation, 

 especially when the fleece or hide is dry (wool-sorters' disease). 

 Some observers (Morris)* have considered that bloodsucking 

 flies are responsible for transmitting infection, but it is very prob- 

 able that this possible source of anthrax has been largely over- 

 estimated. Evidence has also been brought forward to show that 

 infection may be distributed by carrion- feeders, thus anthrax spores 

 have been recovered from the fseces of a dog 6 days after the 

 material was fed, from the faeces of swine after 5 days, &c. 



The period of incubation is probably not longer than 3 days 

 naturally in the horse and ox. Sheep fed on large quantities of 

 spores usually die in 2 or 3 days, but the period is longer than this 

 naturally owing to the doses of infective material being smaller 

 (Hutyra and Marek). The rate of mortality is difficult to 

 estimate ; it is probably about 80 per cent. 



There is not the least doubt but that many animals become 

 affected and recover. Such instances have been recorded person- 

 ally to the author, and in this connection it is interesting to note 

 what the Chief Veterinary Officer of the Board of Agriculture 

 * Journ. Comp. Path., 1918, Vol. XXXI., p. 134, Abs. 



