D&C 46

Two of the gifts of the Spirit are -

"...to some it is given to have faith to be healed;
20 And to others it is given to have faith to heal."  (Doctrine and Covenants | Section 46:19 - 20)

The gift of faith to heal is not restricted to those that hold the priesthood.  The Prophet Joseph Smith said -

“if the sisters should have faith to heal the sick, let all hold their tongues, and let everything roll on.” (Teachings of the Prophet Joseph Smith, page 224.)