The present invention relates to quaternary ammonium disinfecting cleaner compositions comprising a quaternary ammonium compound, an antimicrobial amine, and an anionic scale inhibitor. Beneficially, the compositions provide sanitizing efficacy without diminished performance and without scale formation when diluted with hard water. The compositions are suitable for inactivating and/or reducing infectious agents, particularly Norovirus, Adenovirus, and Polyomavirus.