Severely affected hand nurse holds (7)
I believe the answer is:
smitten
'severely affected' is the definition.
(I've seen this before)
'hand nurse holds' is the wordplay.
'hand' becomes 'mitt' (synonyms).
'nurse' becomes 'sen' (abbreviation for Senior Enrolled Nurse).
'holds' indicates putting letters inside.
'mitt' going inside 'sen' is 'SMITTEN'.
(Other definitions for smitten that I've seen before include "Hit (by remorse, love)" , "Struck (by love?)" , "Afflicted by foolish fondness" , "Deeply in love" , "Captivated" .)