Home health aides certified prior to July 1, 1998, shall, as a condition of renewal of their certificates, undergo a criminal background check pursuant to Section 1736.6 of the Health and Safety Code. Commencing July 1, 1998, pursuant to Section 1736.6 of the Health and Safety Code, home health aide applicants whose applications are submitted on or after July 1, 1998, shall undergo a criminal background check.