INFECTIOUS DISEASES 427 



742. Measles. Measles starts like a common cold, and 

 on about the fourth day of the disease red spots appear 

 over the whole body. The sickness is so mild that little 

 attempt is usually made to control its spread. Yet it may 

 weaken the body so that pneumonia, kidney diseases, and 

 other severe forms of sickness may follow it, and thus it 

 is the cause of thousands of deaths each year. Its germs 

 are not usually long-lived. The disease would soon be 

 suppressed if every case of measles were kept away from 

 other persons for two weeks, and if everything about the 

 sick room were kept clean and well aired. 



743. Scarlet fever. Scarlet fever is one of the most 

 dangerous of the contagious diseases, and yet it does not 

 cause more deaths than measles, for most persons fear it 

 and take pains to suppress it when it appears in a town. 

 It usually comes on suddenly and produces vomiting and 

 pains in the head and back. Fine red spots appear on the 

 skin within a day or two, and there is a sore throat due to 

 spots in the mouth. After the disease is at an end, coarse 

 flakes of the outer skin peel off for two or three weeks, in 

 even the mildest cases. When we are in doubt if a person 

 has the disease, we should wait to see if the skin peels off. 

 Scarlet fever may be suppressed by strict quarantine and 

 cleanliness. 



744. Chicken pox. Chicken pox is a common disease in which 

 small spots like blisters appear on the skin. It seldom causes a severe 

 sickness, and yet it is important, for it closely resembles mild smallpox. 

 It is very rarely seen in grown persons, and so if a grown person seems 

 to have it, the disease is likely to be smallpox. It may be suppressed 

 by keeping the sick at home and away from those who have not had it. 



745. Smallpox. Smallpox was once one of the most 

 common and deadly of all forms of sickness. Before the 

 year 1800 it had often swept over Europe in waves of 



