Any person licensed to practice social work in this state who has retired or may hereafter retire from such practice is not required to maintain that person's licensure as required by this chapter; provided, that the person files with the board an affidavit on a form, prescribed by the board, which affidavit states the date on which the person retired from the practice and such other facts as are required by the board. If the person thereafter reengages in the practice of social work, the person shall renew that person's license with the board as provided by this chapter.