438 MILK 



bacilli may be present in milk in large numbers without materially- 

 changing the taste, odor, and appearance of the milk. Like other 

 bacteria, typhoid bacilh rise with the cream, and in this case 

 cream may become highly infectious. If infected cream is used 

 in tea and coffee the danger from typhoid bacilU is lessened, since 

 both are usually consumed hot — say 60° to 70° C. However, the 

 menace is by no means entirely eliminated. 



Typhoid fever is an intestinal disease and the dejecta and 

 urine of patients or carriers are, therefore, the chief sources of 

 infection. The organisms are abundant in feces and the urine 

 is sometimes so heavily charged that it is turbid. In carriers the 

 discharge is intermittent and the milk is infected at intervals, a 

 circumstance which makes it difficult to detect the true source of 

 infection. 



Infection of milk by carriers, ambulant cases, or persons in the 

 incubation period of the disease is due to lack of cleanhness. The 

 utensils, bottles, and caps may be infected by contact. A further 

 menace lies in the use of polluted water for washing utensils, 

 especially in small dairies where steam is not available. 



When the dejecta of typhoid patients are used for manuring 

 the soil, typhoid bacilli may hve a long time. How an epidemic 

 may be started under such conditions is illustrated in the above- 

 mentioned typhoid fever epidemic in Springfield, Mass. Rain 

 may wash typhoid bacilh from the field into wells, and if this water 

 is used for washing utensils infection becomes possible. Jordan 

 and Irons have reported an epidemic of typhoid fever in La- 

 Grange, 111., which they traced to an infected shallow well. 



Milk-borne typhoid fever epidemics have been traced to car- 

 riers in many instances. Thus Parker found that in an outbreak 

 in Belleville, 111., 86.3 per cent, of all cases had milk from one 

 dairy, and Jordan and Irons reported that in the Hoopeston, 111., 

 epidemic, out of a total of 96 cases, 62 were traced to one dairy 

 and 18 to another one. In both epidemics carriers were the causes 

 of the infection of the milk. 



Senftner reports an epidemic of typhoid fever due to the 

 milk-supply in Bakersfield, California. This epidemic extended 

 over a period of more than a year. It was caused by a carrier 

 and was intermittent in intensity, owing to the well-known 

 fact that the bacilli appear periodically in the discharges of 

 carriers. 



That infected water used for washing utensils may become the 

 cause of milk-borne typhoid fever is shown in an outbreak at 

 Colusa, CaUformia, reported by Geiger. 



Swithinbank and Newman give the percentages of milk-borne 

 typhoid fever epidemics due to various causes as follows: 



