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 know nothing 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 an anagram.
'nigh' becomes 'near' (similar in meaning).
'fever' is an anagram of 'verfe'.
'verfe' inserted within 'near' is 'NEVER FEAR'.

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I've seen this clue in the Evening Standard.

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