Concerned with virus? A way to turn back NICE elaborated (10)
I believe the answer is:
pathogenic
'concerned with virus?' is the definition.
(pathogenic means relating to viruses or diseases)
'a way to turn back nice elaborated' is the wordplay.
I cannot really understand how this works, but
'a' is within the answer.
'way' could be 'n' (Compass direction - North) and 'n' is found in the answer.
'turn' could be 't' (abbreviation in Oxford Dictionary of Abbreviations) and 't' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
(Another definition for pathogenic that I've seen is " Causing disease".)