DISEASES OP THE OX AND SHEEP. 323 



especially in its relations to lower animals partly obtained in the 

 course of inspections made for the Local Government Board in 

 1886. The report is of such great importance to the community 

 as to justify us in making the following abstract of it : — 



Though much has been learned respecting conditions favour- 

 ing its spread and fostering its virulence, still little or nothing 

 IS known of the beginnings of diphtheria. The earliest cases 

 which occur in an epidemic of diphtheria are frequently very 

 mild, and the first persons who die are almost invariably 

 children who are generally supposed to have suffered from 

 *' croup/' and indeed it may be that at the commencement of an 

 outbreak diphtheria may be mainly a local disease, causing death 

 rather by suffocation than by its general effects upon the 

 system. The disease is propagated by personal communication, 

 where circumstances are favourable, as by association of chil- 

 dren in school. Slight cases, and even convalescing patients, 

 may serve to cause very intense disease in other subjects. Thus, 

 when a school has been closed owing to the existence of diph- 

 theria among the scholars, the disease may recur again and again 

 after the re-opening of the school. Children who are convalescent 

 after an attack of diphtheria do not seem to do much harm in their 

 own families, but as soon as a few of them congregate in school 

 the disease is apt to reappear with great severity. 



Over-crowding, badly-trapped drains, damp walls and floors, 

 all tend to enhance the severity of diphtheria, as also does 

 saturation of the soil under the dwelling with fecal matter or 

 with water contaminated with excrement. Cases seem to occur, 

 however, for which neither personal communication nor any of 

 the above conditions can be traced, and the question arises : — 

 "Is there no other possible source of diphtheria? " The com- 

 munication of the diseases respectively known as anthrax and 

 glanders from certain lower animals to man has long ago been 

 established beyond any possibility of doubt. By the medium 

 of cows' milk, scarlatina, diphtheria, and enteric fever have been 

 transmitted to the human subject, and recently Dr. Klein has 

 proved that a disease of the cow, which causes the animal 

 little or no discomfort, can by the channel of the infected cow's 

 milk reproduce itself in man as scarlet fever, one of the best- 

 known and most fatal of infectious disorders. The cow disease 

 in question is of a trivial nature. 



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