DISTRIBUTION OF DISEASE GERMS 



89 



22 per cent had an 

 average of 2500 bac- 

 teria upon each loaf. 

 Of the specimens of 

 wrapped bread, 45 

 per cent averaged 

 848 bacteria to the 

 loaf, and 55 per cent 

 averaged 371. Obvi- 

 ously, if the fresh 

 loaves are wrapped 

 in clean paper, bread 

 will be a much less 

 important carrier of 

 bacteria. 



Few of the bacteria 

 upon the samples of 

 bread were found to 

 be disease-producing, 

 but unclean bread is 

 not especially attrac- 

 tive, even if its load 

 of bacteria does con- 

 tain but few that pro- 

 duce disease. 



A careful study of 

 other common food 

 substances which are 

 handled by many per- 

 sons, or not carefully 

 handled, might pro- 

 duce equally striking 

 evidence regarding 

 the distribution of 

 bacteria. 



FIG. 47. A crowded city block 



The dark areas represent buildings. These buildings 



house 1600 persons, and in such crowded quarters 



it is difficult to prevent the spread of disease. After 



Report of the Department of Health of Chicago 



