SUPPURATION 311 



meteorological conditions and milk, though an open question, may- 

 be an essential one to the origin of the disease. Milk is probably 

 a common vehicle of infection (Ballard, Del6pine, Newsholme), and 

 a number of outbreaks are now on record which appear to have been 

 due to the consumption of contaminated milk. In 1892 Gaffky 

 recorded an outbreak at Giessen,* in 1894 Niven reported on 160 

 cases of diarrhoea at Manchester,! ^^ 1S95 and 1898 three outbreaks 

 occurred at St Bartholomew's Hospital.^ 



The facts set forth above furnish sufficient indication of the 

 appropriate methods of prevention. 



Suppuration and Abscess Fopmation 



The term suppuration is used to designate that general breaking 

 down of cells which follows acute inflammation. An "abscess" 

 is a collection, greater or smaller, of the products of suppuration, 

 pus. Pus consists chiefly of two kinds of cells. First, leucocytes, 

 which have immigrated to the part affected; and secondly, broken 

 down and necrosed elements. Such an advanced inflammatory 

 condition may occur in any locality of the body, and it will 

 assume different characters according to its site. There are 

 connected with suppuration, as causal agents, a variety of bacteria. 

 Pus is not matter containing a pure culture of any specific species, 

 but, on the contrary, is generally filled with a large number of 

 different species, each playing a greater or lesser part in the process. 

 The most important are as follows : — 



1. The Staphylococcus group. — This species consists of micrococci 

 arranged in groups, which have been likened to bunches of grapes 

 (Plate 30, p. 398). They are the common organisms found in pus, and 

 were, with other auxiliary bacteria, first distinguished as such by Pro- 

 fessor Ogston of Aberdeen. There are several forms of the same species, 

 differing from each other in certain respects. Thus we have the S. 

 pyogenes aureus (golden-yellow), alius (white), citreus (lemon), and 

 others. They occur commonly in nature, in air, soil, water, as well as 

 on the surface of the skin, and in all suppurative conditions. The 

 aureus is the only one credited with pathogenic virulence. It occurs 

 in the blood in blood-poisoning (septicaemia, pyaemia), and is present 

 in all ulcerative conditions, including ulcerative disease of the valves 

 of the heart. The Staphylococcus cereus alius and S. cereus flavus are 

 slightly modified forms of the S. pyogenes aureus, and are differenti- 

 ated from it by the fact of their being non-liquefying. They produce 

 a wax-like growth on gelatine. 



* Deut. Med. Woch., vol. xviii. p. 14. 



f Annual Report Medical Officer of Health, Manchester, 1894. 

 J lieport of Medical Officer of Local Government Board, 1895-96, pp. 197-204 ; 

 ibid., 1897-98, p. 235 ; and ibid., 1898-99, p. 336. 



