MUNICIPAL HYGIENE 291 



some of its members are so careless as to expose others. 

 Moreover, many cases of contagious disease cannot be 

 easily recognized as such in the beginning. Conse- 

 quently, a number of persons may be exposed without 

 knowing it. Against the carelessness of its members, 

 the community as a whole can take certain measures of 

 protection, since no one member has a right to endanger 

 the lives of others. It can, for example, demand the 

 isolation of all cases of contagious disease ; the quaran- 

 tine of all those who have been in contact with the 

 disease until it has been proved that they have not caught 

 it ; and the disinfection of the premises at the end of an 

 illness. It can guard against epidemics 1 by such pre- 



1 Influence of vaccination upon smallpox: 



Before vaccination Population Boston Cases Deaths 



1721 11,000 5,989 850 



1730 15,000 4,000 509 



After vaccination 



1811-1830 14 



Annual rate of cases per million of inhabitants: 



Before Optional Compulsory 



Sweden 2,045 480-155 5-0.2 



England 2,000 417 53 



Prussia 2,000 300 4 



Spain 12,050 



Porto Rico 600 



Smallpox cases and death rates per 1,000 persons in Sheffield, 

 Eng., epidemic: 



Cases Deaths 



Not vaccinated 94 51 



Once vaccinated 19 1 



Twice vaccinated 3 0.08 



Children under 10 yrs. 



Not vaccinated 101 44 



Vaccinated 5 0.09 



Influence of antitoxin treatment upon diphtheria (at Boston 

 City Hospital ) : 



Annual death rate per 1,000 cases for 6 yrs. previous to in- 

 troduction of antitoxin ( 1894) 400 



Average death rate for 1904 (excluding cases which died 



within 24 hrs.) 69.5 



