TYPHOID FEVER. 



be regarded as an unusual, rather than a common, source of 

 such epidemics. 



TYPHOID FEVER. 



Typhoid fever is probably more frequently distributed by 

 milk than any. other definite disease. The disease is easily 

 recognized, the bacillus which produces it is well known, and 

 it has been demonstrated by conclusive evidence that typhoid 

 epidemics have been frequently distributed through the 

 medium of milk. There have been over one hundred such 

 epidemics of typhoid traced to a milk supply. The force of 

 the evidence that the milk supply has been the cause has 

 varied ; sometimes the facts are practical demonstrations, and 

 in other cases only suggestive. 



It is important to recognize at the outset that the only 

 source of typhoid bacillus in milk is from external con- 

 tamination. The cow, so far as known, never has typhoid 

 fever or any symptoms of disease produced by the growth 

 of this organism. Milk is, therefore, never contaminated 

 with these bacteria when first drawn, and all contamina- 

 tion comes from secondary sources. 



Typhoid bacilli find their entrance into milk from two 

 common sources. The first is from some employee of the 

 dairy who has the mild form of typhoid fever known as 

 " walking typhoid." In such cases the disease is so mild as 

 to fail to confine the person to his room, and allows him 

 to continue about his work as usual. Such persons work- 

 ing in a dairy and handling the milk or milk vessels are 

 an immediate danger to the neighboring community. The 

 second source is the water. Where milk is watered the pos- 

 sibility of such infection is easily seen. But it is by no means 

 necessary that the milk should be watered in order that the 

 water may be a source of typhoid contamination. Milk cans 

 which are washed in well water or brook water, or rinsed in 

 water from these sources, may occasionally become infected 

 with typhoid bacteria, provided the source of the water itself 



