PATHOGENICITY FOR MAN 



217 



Organism found 

 Pneumococcus 

 Streptococcus 

 Friedlander's bacillus 

 Influenza bacillus 

 Staphylococcus 

 Mixed infections 



Total 



3,319 



100.0 



Heffron in a searching inquiry into the part played by the various 

 serological types in the causation of lobar pneumonia collected all 

 the available data and presented analyses of the figures obtained. 

 In 14,869 cases of the disease reported from many parts of the 

 world, pneumococci of Type I occurred in 32.8 per cent; Type II 

 in 20.6 per cent; Type III in 10.8 per cent; while all organisms 

 listed under Group IV were found in 35.8 per cent of the cases re- 

 ported. The incidence of pneumococcal types in lobar pneumonia 

 arranged according to geographic distribution, as far as reported, 

 may be seen in the table taken from Heffron. 601 



PERCENTAGE DISTRIBUTION BY SEROLOGICAL TYPE OF 14,869 



CASES OF PNEUMOCOCCUS LOBAR PNEUMONIA IN 



CERTAIN GEOGRAPHIC AREAS 



