1915] on Anti-Typhoid Inoculation 433 



organisms are injected, the amount of amboceptor present Avitli tliem 

 enables the complement of the inoculated person's blood to destroy 

 the bacilli with speed and certainty and without any danger of a 

 general infection resulting (diagram d). 



Injection of living organisms has not commended itself to bac- 

 teriologists in this country, and the method has not been adopted 

 o-enerallv. 



C— The Results of Axti-Exteric Ixoculatiox. 



We now turn to the results following this prophylactic measure, 

 and they are best dealt with under the headings of (a) the early and 

 {h) the remote effects. 



{a) The early Results. 



The most immediate, and in some ways the most practical, results 

 are the reactions occurring in the inoculated. After considerable 

 experience one can summarize the results as regards incapacitation as 

 follows : 



Incapacitated for five days, 1 per mille. 



Incapacitated for three days, 3 per mille. 



Incapacitated for less than three days, 99G per mille. 



If due care be exercised, the danger of a reaction necessitating 

 the man being admitted to hospital is almost negligible, and one 

 force (I think it was the Canadian contingent) recently reported the 

 inoculation of 27,000 men without a single hospital admission. 



The constitutional reaction comes on usually about six hours 

 after inoculation, and consists of malaise, a slight temperature of 

 perhaps 101°, with — in some cases — a tendency to faintness. If the 

 man turns in early, he will probably sleep through the stage of 

 constitutional reaction without being conscious of it. 



The redness, tenderness and oedema around the inoculation site 

 usually begin to subside after twenty-four hours. 



It is safe to say that in 99 per cent of cases the man is capable 

 of carrying out his duties at the end of forty-eight hours. 



The Stood changes follow later, and are of both scientific and 

 practical interest, seeing that upon them depends the efficacy of the 

 protection conferred by this method of prophylaxis. 



The essential change is an increase in the amount of protective 

 substances of the amboceptor group. It will serve if one substance 

 of this complex group — the agglutinin — be used to illustrate both 

 the degree of immunity conferred and the methods of estimation. 



Agglutination is the phenomenon by which motile organisms in 

 the presence of agglutinins first lose their motility and then collect 

 together in groups, as if for mutual protection. Hanging-drops 

 demonstrate both the initial motihty and the complete agglutination 



