Vice can change treatment for virus (7)

I believe the answer is:

vaccine

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'treatment for virus' is the definition.
I can't tell whether this definition defines the answer.

'vice can change' is the wordplay.
'change' is an anagram indicator.
'vice'+'can'='vicecan'
'vicecan' with letters rearranged gives 'VACCINE'.

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(Other definitions for vaccine that I've seen before include "Vice can create protection against disease" , "Preparation for inoculations" , "Antigenic preparation" , "preparation for pandemic?" , "Antibody stimulator" .)

I've seen this clue in The Daily Express.

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