The Microbe is a 1919 American silent comedy-drama film, directed by Henry Otto. It stars Viola Dana, Kenneth Harlan, and Arthur Maude, and was released on July 21, 1919.

• Viola Dana as Happy O'Brien, aka "The Microbe"
• Kenneth Harlan as DeWitt Spense
• Arthur Maude as Robert Breton
• Bonnie Hill as Judith Winthrope
• Ned Norworth as Norman Slade
• Lucy Donahue as Mrs. Risden

• The Microbe at IMDb
• The Microbe at the TCM Movie Database
• The Microbe at the AFI Catalog of Feature Films