1 8 THE POPULAR SCIENCE MONTHLY 



careless mingling with friends and neighbors when at the beginning or 

 end of an attack of communicable disease. The isolation of even frank 

 cases of the so-called mild diseases is still too often regarded as an 

 unreasonable imposition by the uneducated (and the uneducated are by 

 no means always those of the most limited incomes). We still hear 

 " Every one must have measles and the children might as well have it 

 as soon as possible." There has seldom been a more cruel superstitution. 

 The children's diseases, measles, scarlet fever and whooping cough are no 

 light matter. Each one of them kills more victims than smallpox, and 

 in many cities often more than typhoid fever. In New York City in 

 1912, there were two deaths from smallpox, 500 from typhoid, 671 from 

 measles, 614 from scarlet fever and 187 from whooping cough. Fur- 

 thermore, the seriousness of these maladies decreases directly with the 

 age of a child, so that each year for which an attack may be postponed 

 is so much gained. With the progress of health education in the public 

 schools we may look for the day when the social crime of spreading 

 communicable disease will be realized at its full value, so that it will 

 be recognized as wanton recklessness, not courage, to continue business 

 or social intercourse when "coming down," half-sick with some as yet 

 undefined but impending disease, and no thoughtful person will hasten 

 to mix with his fellows when possibly still a carrier after an attack. 

 In all these diseases there are two factors, the invading germ and the 

 more or less susceptible host, and even a common cold is often due less 

 to poor vitality than to fresh and virulent infection. Some day, per- 

 haps, responsibility may be felt for the reckless dissemination of even 

 this supposedly mild disease, of which Dr. Eosenau well says in his 

 recent work on " Preventive Medicine and Hygiene " : u Could the sum 

 total of suffering, inconvenience, sequelae and economic loss resulting 

 from common colds be obtained, it would at once promote these infec- 

 tions from the trivial into the rank of the serious diseases." 



It is of course, not essential that " isolation " of an infected person 

 should mean solitary incarceration within four walls. In the Middle 

 Ages the only protection against disease was quarantine, which in its 

 derivative meaning was forty days' detention of all persons, well or sick. 

 coming from an infected port. With the progress of sanitary science 

 preventive measures have become at the same time more efficient and 

 less irksome. When ships from cholera countries came to our eastern 

 seaports two years ago, only a detention of a day or so was necessary, 

 pending a bacteriological examination of the passengers and detection 

 of the few carriers among them. Isolation of individuals takes the place 

 of quarantine against nations, and a practical isolation may often be 

 effected by simple precautions against the transfer of discharges, with- 

 out interference with human intercourse. Disease germs do not fly 

 across a room to seize on their prey. They are carried by direct mate- 

 rial contact of some sort, by the discharge of mouth spray, by hand 



