In sickness and in health

is part of the promise made in the Marriage Service from the Book of Common Prayer.

Avoid like the plague means keep right away from.  The plague is an extremely infectious life-threatening disease.

The itch, the pitch, the palsy and the gout are all illnesses or disabilities.   The itch makes people scratch.  The pitch sounds as if they fall over.  The palsy is a shaking or paralysis as in Bell’s palsy and gout is an inflammation usually of a toe joint.

Out of sorts means not feeling well or in a bad mood.

Proper poorly is used in Northern England where Southerners might say “Not very well at all”.

Loosen tight clothing is one of the first instructions First-aiders learn.

The cure is worse than the disease
is a saying which is sometimes true.

Rub salt in a wound is a metaphor.  Salt has antiseptic properties, but stings.  The metaphor is about what is said.

Accidents happen even in the best regulated households
is an expression I grew up with.

Accidents don’t happen; they are caused.
This is an alternative point of view, which I have come across recently.  Of course, it is sensible to work safely and avoid obvious dangers.

An accident waiting to happen is an expression frequently used.

Keep body and soul together means stay alive.  Food and drink are essential for this.  After a good meal someone may joke, “That will keep body and soul together!”

The halt and lame cannot walk very well.  The expressions blind and lame and  halt and maimed come from the Authorised Version of the Bible.  Luke 14:13-14 and Matthew 18: 7-9