Set limits on disease and inertia (9)
I believe the answer is:
stillness
'inertia' is the definition.
(inertia is a lack of movement)
'set limits on disease' is the wordplay.
'limits' says to hollow out the word (remove centre letters).
'on' means one lot of letters go next to another.
'disease' becomes 'illness' (illness is a kind of health problem).
'set' with its middle taken out is 'st'.
'st'+'illness'='STILLNESS'
'and' acts as a link.
(Other definitions for stillness that I've seen before include "Lack of movement" , "Quiet, calm" , "Tranquil silence, calmness" , "Immobility" , "Tells sins in motionless silence" .)