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long confused witli typhus fever ; very recently another disease has been 

 differentiated, known as paratyphoid. Thus iiner and finer distinctions are 

 being made. In this connection I might refer to the analogous case of 

 the plants Scrophularia nodosa, Scrophularia Marylandica, and Scroph- 

 ularia leporella. and how the latter, a native Indiana plant, was for a long 

 time confounded with the other, just as that in turn had been confused 

 with the European form — a botanist will readily understand this simple 

 allusion. 



Malaria and typhoid fever botli flourish under simjile and primitive 

 conditions, that is, under a neglect of sanitation. Malaria flourishes 

 where the Anopheles moscpiito breeds and is transferred from one indi- 

 vidual to another by its bite. The drainage of wet places and the use of 

 (luiniue are the chief factors that account for the subsidence of malaria 

 and its present I'arity. Typhoid fever differs markedly from malarial 

 fever in that one attack protects the individual. The weak are killed off 

 and those who survive are innnune (second attacks of the disease lieing 

 rare) and this fact has an important bearing. Typhoid fever is chiefly a 

 water-borne disease, especially well water. Where wells and closets are 

 close together or where the subsoil is porous, diffusion takes place. In a 

 family where typhoid fever occurred there may be no further difliculty 

 from the use of the well water, but any stranger or visitor using it may 

 fall a victim. In cities dependent on wells there maj' be much typhoid 

 fever, while on the other hand a city with a good municipal water supply, 

 especially ^vhere the water is properly filtered, may have little of it. Cities 

 dependent on a river supply without previous filtration may fare very well 

 so long as the water is clear, but with the muddying of the river after a 

 rain and with a resort of the citizens to the old wells, there may be a 

 constant recurrence of the disease. In this connection we must not forget 

 that many of our rivers are today nothing but open sewers full of infec- 

 tious germs. 



Malaria has disappeared from the cities (the Anopheles mosquito does 

 not live in cities) but it still flourishes in backward, undrained, communi- 

 ties — communities that are still in the Dog fennel days. On the other 

 hand, typhoid fever is all too connnon in some of our cities and towns — 

 another indication of the survival of Dog fennel days. 



Not so very long ago the chief diagnostic character for distinguishing 

 between the two diseases was the fever, that is the elevation of tempera- 

 ture, but every now and then so-called atypical cases occurred which left 



