118 THE HOUSE FLY DISEASE CARRIER 



organs of the fly and may be deposited with its excre- 

 ment." 



There were many other important conclusions which 

 bear upon the fly question. For example, it was shown 

 that every regiment in the United States service in 

 1898 developed typhoid fever, nearly all of them within 

 eight weeks after assembling in camps. It not only 

 appeared in every regiment in the service, but it be- 

 came epidemic both in small encampments of not more 

 than one regiment and in the larger ones consisting of 

 one or more corps. All encampments located in the 

 Northern as well as in the Southern States exhibited 

 typhoid in epidemic form. The miasmatic theory of 

 the origin of typhoid fever and the pythogenic theory* 

 were not supported by the investigations of the com- 

 mission, but the doctrine of the specific origin of fever 

 was confirmed. The conclusion was reached that the fe- 

 ver is disseminated by the transference of the excretions 

 of an infected individual to the alimentary canals of 

 others and that a man infected with typhoid fever may 

 scatter the infection through every latrine or regiment 

 before the disease is recognized in himself, while germs 

 may be found in the excrement for a long time after 

 the apparent complete recovery of the patient. Infected 

 water was not an important factor in the spread of 

 typhoid in the national encampments of 1898, but about 



This theory is founded upon the belief that the colon germ 

 may undergo a ripening process by means of which its virulence 

 is so increased and altered that it may be converted into the 

 typhoid bacillus or at least may become the active agent in the 

 causation of typhoid fever. 



