It's not written correctly but the meaning is, if you know you or yourself are to become ill, or more ill than you already are, it's good to have a nurse who can help you.

Hi, this line comes from Hillaire Belloc’s poem “Jim (who ran away from his Nurse and was eaten by a Lion)”. Jim's father advises small children to “always keep a-hold of Nurse, for fear of finding something worse”. A nurse is like a nanny who looks after children.

you have a sense of humor