8 THE PRESIDENTIAL ADDRESS. 
bacilli had much the same effect. This substitution of the dead bacilli 
for the living was a great advance in the method, being much simpler 
“and much safer. : 
The next disease to be attacked by this method was typhoid fever. 
This was initiated by Sir Almroth Wright at the British Army Medical 
School, and carried out with that scientist’s characteristic ability and 
energy. The method was mainly directed in the first place to lessen the 
mortality from this disease among our soldiers serving in India. 
After several years’ experience, the mode of inoculation which was 
finally settled on was to give two injections of dead typhoid bacilli, one of 
500 millions, and a second, at an interval of ten days, of a thousand millions. 
Now let us see what effect anti-typhoid inoculation has had on the 
prevention of typhoid fever among our soldiers in the field. 
In the South African War, at the beginning of the century, before the 
method had been developed, in an army the average strength of which was 
only 208,000 there were 58,000 cases of typhoid fever and 8,000 deaths. 
In the Great War, on'the Western Front, with an average British strength 
of one and a quarter millions, there were only 7,500 cases and 266 deaths. 
In other words, there were fewer cases of the disease in this war than there 
were deaths in the South African. 
It is also interesting to learn from French sources that at the beginning 
- of the war the French soldiers were not inoculated, whereasthe British were. 
The result for the first sixteen months was striking. During this time the 
French had some 96,000 cases, with nearly 12,000 deaths. The British had 
only 2,689 cases and 170 deaths. Afterwards the French soldiers were very 
thoroughly vaccinated, with the result that their immunity eventually 
became as striking as our own. 
What the number of cases and death-rate from typhoid fever might 
have been in the huge armies fighting on the different fronts had it not 
been for this preventive inoculation it is impossible to say, but undoubtedly 
the suffering and loss of life would have been enormous. 
I may therefore conclude this account of anti-typhoid inoculation by 
saying that it certainly constituted one of the greatest triumphs in the 
prevention of disease during the recent war. 
Tetanus and Diphtheria. 
I shall now pass on to consider a third method of preventing bacterial 
diseases which has also been evolved during the time under review ; 
that is, by the injection of specially prepared blood sera. These are known 
