Disease might massage Ms Fitzgerald (7)
I believe the answer is:
rubella
'disease' is the definition.
(rubella is a kind of health problem)
'massage ms fitzgerald' is the wordplay.
'massage' becomes 'rub' (I've seen this in another clue).
'ms fitzgerald' becomes 'ella' (I've seen this before).
'rub'+'ella'='RUBELLA'
'might' is the link.
I am not very happy about this link. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for rubella that I've seen before include "contagious disease" , "German measles" , "complaint" , "infection" .)