I’m nervous about being infested (9)

I believe the answer is:

verminous

'infested' is the definition.
(infested with vermin)

'i'm nervous about' is the wordplay.
'about' indicates an anagram.
'im'+'nervous'='imnervous'
'imnervous' anagrammed gives 'VERMINOUS'.

'being' acts as a link.

(Other definitions for verminous that I've seen before include "ratty" , "Like fleapit" .)

I've seen this clue in The Times.

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