As long as the hen in question is eating and drinking, acting normal like a chicken should, I wouldnt be too concerned. Since we both live in the same area and it's springtime, and how warm and moist our soil is...consider worming your birds. I wormed mine last week.
Thanks Dawg53 she was a stray and has had no treatments so will check into worming. Surely couldn't hurt in our environment. Do you buy locally or online?