This circle game from the British Isles has Irish and Scottish variations and seems to refer to a deadly measles outbreak, of which there were many recorded in the 1700s and 1800s.
Source: Locke, Eleanor G. Sail Away: 155 American Folk Songs to Sing, Read, and Play. p. 16
Information about measles outbreaks from the Keighley and District Family History Society website which cites statistics from the Australian Institute of Genealogical Studies.
