With the raging fever nigh contained, stop worrying (5,4)

I believe the answer is:

never fear

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'contained stop worrying' is the definition.
I don't know anything about this answer so I cannot judge whether this works.

'with the raging fever nigh' is the wordplay.
'with' means one lot of letters goes inside another.
'the raging' indicates anagramming the letters.
'nigh' becomes 'near' (similar in meaning).
'fever' anagrammed gives 'verfe'.
'verfe' inserted into 'near' is 'NEVER FEAR'.

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I've seen this clue in the Evening Standard.

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