VACCINES IN PROPHYLAXIS OF DISEASE 205 



ease of young persons. Of 1,000 deaths from 

 typhoid fever collected from the registration 

 area of the United States, one-third occurred in 

 persons under twenty years of age and one-fifth 

 in those under fifteen years. Typhoid vaccina- 

 tion among young children is increasing rapidly 

 and, each year, more and more children are be- 

 ing vaccinated against typhoid fever. As a rule, 

 the children do not have to remain home from 

 school or indoors. Sometimes there is slight 

 fever in the vaccinated children. Vaccination is 

 well borne by children, the dose being propor- 

 tioned to the body weight, taking 150 pounds as 

 the unit. 



DIRECTIONS FOR USING TYPHOID VACCINE 



Three doses of the vaccine are given at 7 to 

 10-day intervals. The first dose contains 500 

 million bacteria, the second and third 1,000 mil- 

 lion. In army practice, the 10-day interval is 

 used as most desirable ; but in civil practice, the 

 7-day interval is often more convenient, thus 

 bringing the three doses on three successive 

 Saturday afternoons. Experience has shown 

 that the most suitable hour of the day for vacci- 

 nating is late in the afternoon, since the local 



