https://chroniclingamerica.loc.gov/lccn/sn83045433/1918-12-30/ed-1/seq-1/

The holiday crowds are blamed by the DC health officer for the new influenza outbreak. There are 45 cases in the DC influenza hospital that opened on December 24. Postmaster Burleson is planing on operating a single wire service, combining Western Union and the Postal telegraph.

Source: “Holiday Crowd Blamed for Flu,” The Washington Herald, Washington, District of Columbia, December 30, 1918. Page 1, Column 8.