378 PHARMACEUTICAL BACTERIOLOGY 



truck gardeners are particularly culpable in this regard. Again, the 

 vegetables may be irrigated with stagnant sewage-polluted water. House 

 flies are carriers of typhoid. 



The mortality rate in typhoid is high and the disease runs its course in 

 about five weeks. There are some mild cases, the so-called walking or 

 ambulatory cases. All of the excreta from the patient should be disin- 

 fected. Among the disinfectants which have been used for this purpose 

 are, corrosive sublimate (i-iooo), copper sulphate (5 to 15 per cent.), 

 copperas solution (10 to 20 per cent). These are effective when properly 

 used. Their albumen coagulating coefficient is very high (see table in the 

 chapter on disinfectants) and it is absolutely necessary to stir the mixture 

 of material and disinfecting solution very thoroughly. The noncoagulat- 

 ing disinfectants are to be preferred, such as milk of lime and the coal tar 

 disinfectants. All bed Hnen, clothing, etc., used by the patient should 

 be disinfected in 5 per cent, carbolic acid before washing. Everything 

 used by the patient should be sterilized, disinfected and kept away from 

 the rest of the family. Those who nurse typhoid patients must be ex- 

 tremely careful not to carry the infection to others. Pillows, mattresses 

 and other large articles used by the patient should be steam steriUzed. 

 In simple words, everything about the patient must be scrupulously steri- 

 lized in order to avoid spreading the infection. 



A national department of health should see to it that the water supply 

 of large cities is free from sewage contamination. Our streams, lakes and 

 reservoirs which supply drinking water, require careful guarding against 

 typhoid infection. 



There should be compulsory regulation regarding the position and 

 depth of wells in farm yards and as regards the position of the well relative 

 to barns, cow sheds, privy vaults, etc. Typhoid fever will continue its 

 ravages as long as filth contamination of water supphes and food supplies 

 is permitted. 



The Gruber-Widal test for t3^hoid is an agglutination phenomenon. 

 The agglutinating power of the blood of a typhoid patient is usually 

 noticeable as early as the fifth day of the disease. Preventive inoculation 

 with typhoid bacterin has been used with considerable success, particu- 

 larly in the British and German armies, ane is now quite extensively used 

 in general practice. Chantamesse and Wright use agar or broth cul- 

 tures of the typhoid bacillus, killed by heat. 



The de Silvestri urinary test for typhoid is made as follows: 



In a small test tube overlay 2 mils of ferric chloride to which 

 four drops of concentrated sulphuric acid has been added, with three 

 mils of the filtered urine. If typhoid is present, a more or less 

 maroon colored ring will develop at the zone of contact, and at the 



