DIGESTION OF FOOD : THE INTESTINE 111 



bacteria are well known. Drinking water, if in any way 

 polluted with sewage, is almost certain to contain typhoid 

 germs. Hence, water from brooks, reservoirs, rivers, lakes 

 or wells that receive any sewage is unsafe to drink. 



Milk is also a source of typhoid infection. If there is a 

 case of typhoid fever at a farm where milk is produced, the 

 germs are pretty sure to get into the milk. Oysters which 

 have been placed near the mouth of a river for the sake of 

 "floating" them are also occasionally infected with the bac- 

 teria, and if eaten uncooked, cause the disease. Flies are apt 

 to carry the germs on their feet and deposit them on the food 

 upon which they feed. 



t o avoid the dangers of typhoid fever one should drink none 

 except the purest water, be especially careful of the milk sup- 

 ply, and not allow flies to alight on food or dining tables. Both 

 water and milk can be made perfectly safe by boiling. 



A very successful method of avoiding typhoid fever is by an 

 inoculation with anti-typhoid vaccine. This is injected under 

 a person's skin and thus renders him immune against typhoid 

 fever for two or three years. It is very widely used with 

 soldiers, and it is wise for persons who are to travel, where 

 they cannot properly control their food and water, to thus 

 protect themselves. 



Hookworm. This disease is caused by a small parasitic 

 worm. A person becomes infected sometimes by taking these 

 worms into the mouth with food or drink, but more com- 

 monly by getting dirt containing them onto the hands or feet. 

 They usually find their way to the intestine where they may 

 live for a long time. The symptoms of the disease are a dry or 

 yellow skin, anaemia (paleness), stupid facial expression, emacia- 

 tion, irregularities in appetite and breathing, weakness in the 

 muscles, headache, defective mentality, and some others. The 

 disease is quite easily cured by treatment with thymol. This 

 disease is very common in the South, especially among those who 

 go barefoot, since they are very easily infected through their feet. 





