A streetcar of the Philadelphia Transit Company has a sign that reads: "You Did It - Mr. Citizen! You, the City Government and the P.R.T. Employes Made Sidewalks Cleaner. Keep at It, Co-Operate, Don't Spit"
Streetcar with "SPIT SPREADS DEATH" sign. The Philadelphia Rapid Transit Company worked closely with the Department of Public Health to try to cut back on the spread of influenza. Note that the windows on the streetcar are open for more ventilation.