When nicest old girl gets nasty disease (10)

I believe the answer is:

asbestosis

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'nasty disease' is the definition.
'asbestosis' can be an answer for 'disease' (asbestosis is a kind of health problem). I'm not certain of the 'nasty' bit.

'when nicest old girl gets' is the wordplay.
'when nicest old girl' becomes 'asbestos' (I am not sure about this - if you are sure you should believe this answer much more).
'gets' becomes 'is' (I've seen this in other clues).
'asbestos'+'is'='ASBESTOSIS'

Can you help me to learn more?

(Another definition for asbestosis that I've seen is " Lung disease".)

I've seen this clue in The Guardian.

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