SECTION III.

AN INVESTIGATION OF INFLUENZA IN BOSTON (WINTER OF 1920.) 127

Diagnostic standards for the 1918 epidemic 134

Standards for 1920 134

Morbidity 137

Relation of sex to morbidity 143

Relation of sex to severity 145

Morbidity by age 145

Relationship of occupation to morbidity 150

Effect of race stock 155

Mortality 156

Mortality by sex 165

Relationship to age 167

Relationship of occupation 170

Density of population 170

Race stock and mortality 173