2024 Yes https://doi.org/10.1186/s12889-024-19656-7 Or, Peggy Pui-Lai Asia Experimental Staff Elementary (K-5) Bacteria Viruses COVID rates Other School health Cleaning method Disposable wipes Cleaning staff Fluorescent mark A three-arm randomized trial tested a school cleaning protocol using markers and swabs. Group A (training + wipes) achieved full cleanliness, outperforming training-only and control groups, showing that training plus materials improves cleaning outcomes.