GERMS 291 



Spores. Following a favorable period of reproduction, certain 

 bacteria enter into a stage known as spore-formation, a single cell 

 usually producing one spore. This is a resting stage. The spores 

 are of dense structure, and offer extraordinary resistance to heat, 

 chemicals and disinfectants. When conditions again are favorable, 

 the spores again enter the reproductive state, but the spore may 

 remain dormant for an indefinite time, as in the case of a typhoid 

 patient, who, after months or years, suffers a recurrence of the 

 disease, due to the development of sleeping spores. 



Multiplication of Germs. When germs have fully developed, 

 a fission takes place which divides the cell into two equal parts. 

 These in turn divide into two parts each. As the fission occurs 

 rapidly, sometimes as often as once in 20 minutes, the multiplica- 

 tion is enormous, sometimes amounting to millions in a day. 



How Germs Enter the Body. Germs may be introduced into the 

 body through : 



1. The sweat glands. 



2. The hair follicles. 



3. The mucous membrane (nose and mouth). 



4. Abrasions in the skin. 



5. Drinking polluted water or milk. 



6. Eating food that contains germs, or has had germs deposited 

 upon it by flies. 



7. Mosquitoes and other insects which carry different disease 

 germs to the body. 



How Germs Cause Disease. Germs produce virulent (vir'u lent) 

 poisons as they grow in the body. These poisons cause toxins. It 

 is the toxins that cause disease, not the germs. 



How the Body Kills Germs. The little white corpuscles of the 

 blood are useful animals. One of their functions in the blood is to 

 kill disease germs by eating them. Sometimes the corpuscles, after 

 swallowing the germs, are unable to digest them, and are killed by 

 them. If this happens, the disease will become worse, and if it con- 

 tinues, the patient will die. If the corpuscles are strong enough to 

 digest the germs, the person usually gets well. There is also a sub- 

 stance which kills germs. Every healthy person has a sufficient 

 quantity of this substance in his body to kill some germs, but not 



