

THE CONTROL OF HEALTH 391 



of communicable diseases. The quarantine period may 

 involve : 



1. The time elapsing between exposure and onset of disease. 



2. Time of actual sickness with the disease. 



3. A detention period after active sickness is past but during 



which the person may be a "carrier," i. e., be a source 

 of infection to others. 



We have already called attention to the "incubation" 

 period of several common diseases in Chapter XXIII. The 

 second period mentioned will differ much with the physio- 

 logical condition and care given the patient, so that little may 

 be said about it in advance. The period of detention also 

 varies but in no case should a person recovering from a com- 

 municable disease be allowed to return to the company of 

 others without permission from a physician. The quarantine 

 law for some minor maladies often reads thus: "Persons 

 suffering from measles, whooping-cough, mumps, German 

 measles, and chicken-pox shall be barred from school for 

 twenty-one days from the onset of the disease." Lessening 

 or lengthening of this period is left to the physician or health 

 officer having jurisdiction. 



Houses in which there are communicable diseases should 

 bear a placard so stating; and the Board of Health should 

 furnish a list of communicable diseases, with the quarantine 

 rules applying to them, to all parents who have children in 

 school. 



Municipal Health and Hygiene. From the standpoint 

 of health, the city has many of the characteristics of the 

 single home. As the ill health of one or two members of a 

 family may endanger the health of the rest, in precisely similar 

 fashion unhealthful conditions in any section of a city are a 

 menace to the whole city. Therefore authority must be 

 given special groups of men who shall act toward affairs of a, ' 

 city as parents do in the affairs of families. 



