Healthy quality nurses did spread (9)

I believe the answer is:

ruddiness

I'm a little stuck... Click here to teach me more about this clue!

'healthy quality' is the definition.
The definition and answer can be both human attributes as well as being singular nouns.
Perhaps you can see an association between them that I can't see?

'nurses did spread' is the wordplay.
'spread' is an anagram indicator.
'nurses'+'did'='nursesdid'
'nursesdid' is an anagram of 'RUDDINESS'.

Can you help me to learn more?

(Another definition for ruddiness that I've seen is " very red face".)

I've seen this clue in The Daily Express.

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