relapse

a sudden and severe return of an illness

measures taken to stop an illness from returning

the frequency at which relapse occurs in a group of people

used to state that a relapse happens

the possibility that a relapse will occur

in a state where an illness has returned after a period of improvement

to stop a relapse from happening

to cause an illness to return, often by a specific event or substance

to undergo the return of an illness, often with a negative connotation

to have an illness or bad habit return

to be the reason for an illness or condition to return

to cause a relapse to happen suddenly or sooner than expected