BACTERIA 309 



with the same disease. 1 It has been discovered that flies 

 and mosquitoes sometimes carry the germs of disease from 

 one person to another. 2 



Again, disease-producing bacteria, as we have learned, 

 may enter the body with the air we breathe, the food we 

 eat, and the water we drink. Thus, as we have seen, the 

 air may be infected with poisonous germs from the dust of 

 dried sputa (Sec. 237). 



1 Ringworm may occur anywhere on the body, but is perhaps most com- 

 mon on the scalp and face. When found on the bearded parts of the face it 

 is called " barber's itch." 



Although ringworm of the face is usually a slight affair, it ought always 

 to be cured as speedily as possible, for it is highly contagious. A child 

 with ringworm should be kept away from school, should sleep alone, and 

 should have special towels, soap, and hair- 

 brush, which the other children in the family 

 should under no circumstances be allowed 

 to use. 



2 During recent years it has been dis- 

 covered that many insects, supposed to be 



harmless, afford one of the ways in which JT IG . I0 r A Piece of Hair 

 infection may occur. During the Spanish- f rom the Scalp infested 

 American war of 1898 it was proved that w i t h a Mold which pro- 

 typhoid fever was spread through the camps duces Ringworm, 

 by the agency of flies. 



These insects, bearing typhoid germs on their feet, would fly to the camp 

 kitchens and there leave the germs on the food prepared for the soldiers. 

 The prevalence of this " camp fever " among troops encamped in high and 

 seemingly healthful regions puzzled the attending surgeons until the true 

 explanation was discovered. 



The mosquito is another insect known to transmit certain diseases ; 

 indeed, it is believed by many to be the principal agent in the spread of yel- 

 low fever and malaria. It does not carry the germs on its feet, as the fly 

 does, but within itself and on its proboscis. It first stings a sick person, 

 taking in the germs with the victim's blood, and then when it next stings 

 a healthy person the germs are communicated to the blood and there 

 develop in great numbers and excite an attack of the disease. 



In India, it has been found that flies carry cholera germs in the same 

 way, wiping them from their feet on food; and it is quite probable that 

 they may carry the germs of dysentery, consumption, and other diseases. 



