Avoid cold and fever? (5)
I believe the answer is:
cheat
'avoid' is the definition.
(as in cheating death)
'cold and fever?' is the wordplay.
'cold' becomes 'c' (eg on taps).
'and' says to put letters next to each other.
'fever?' becomes 'heat' (a fever might make you hot).
'c'+'heat'='CHEAT'
(Other definitions for cheat that I've seen before include "Rogue" , "One dealing dishonestly" , "shark" , "Play dishonestly" , "22 [FRAUDSTER]" .)