SALIENT POINTS.
Period of Life. Most cases occur between 20 and 40 years.
In Schools. The older children are first attacked: open air schools are a positive, but not an absolute defense against Infection.
Indoor Schools. The ratio of prevalence amongst children of all ages is 40%.
Outdoor Schools. All ages, the ratio of prevalence is 10%.
Open Air Occupations. Such as workers in the fields, 12% are attacked.
Closed Rooms. Factory Operatives, 49% are attacked.
MAIN FACTOR OF SPREAD. Not the Weather, but HUMAN intercourse, especially Commerce; the greater the speed of Commerce, the greater and quicker is the spread of the Flu; it follows the path of HUMAN travel; it is a Contagion solely spread by HUMAN intercourse, viz. “The Influenza Carrier or Carriers.”
Positions in life, which require contact with Travelers, necessarily influence and spread the disease.
“Flu” is spread in the same ratio of speed as the Carrier of IT.
When the Flu is a weakling, his best Nurses and Foster-Mothers are Overcrowding and lack of Pure Air.
Where the Crowd is, there the Flu is: little crowding means little Flu; plenty of Crowding, plenty of Flu.