Let's just say I have my doubts.
Here's Ian Munro's mini-FAQ on the subject: http://www.ualberta.ca/~imunro/ring.html
The Urban Legends web site had this to say: http://www.urbanlegends.com/misc/ring_around_the_rosie.html
and the following 3 sites also attempt an analysis of the song:
http://www.geocities.com/Athens/Forum/3041/rosie.html
http://www.gbalc.org/MotherGoose/rhymes/ringaround.html
http://members.nbci.com/nur_rhymes/r019.html
Does it really? Check the actual list of symptoms of bubonic plague, as given by the (American) Center for Disease Control: http://www.cdc.gov/ncidod/dvbid/plagindex.htm
Note that the major symptom of bubonic plague is the swelling (bubo) of the lymph glands near the flea bite. Skin discolouration (as required for the "ring o'roses" line) barely gets a mention. Also note that sneezing doesn't get mentioned at all.
Another important point is that the rhyme itself has mutated over the years: the further back in time you go, the fewer "symptoms" get mentioned. The version claimed to be circulating in 1790 reads like this:
Round a ring of roses,
Pots full of posies,
The one who stoops last
Shall tell whom she loves best.
which doesn't seem to have much to do with the plague.
By my reckoning, no it isn't. For four reasons:
For the song to be about the plague it would have had to remain unrecorded (in print) for over 200 years, and having appeared in print it would have to take a further 80 years for someone to spot the plague connection.
To quote someone far smarter than me: "Does not compute."
True enough: you can't prove a negative.
But I have (I hope) shown that the "plague" interpretation is a rather shaky one.
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