The leading cause of absences in public schools is respiratory infections acquired from other sick students. In hospitals many patients acquire worse infections once they enter the hospital for treatment, than they had when they originally were admitted for sickness.
Anywhere there is a meeting place such as sick clinics, doctor's offices, emergency rooms, or other similar areas there is a need to keep the air clean and surfaces clean.
This video explains how ultraviolet-c range light ( the type of ultraviolet light that does not cause cancer) can be used to stop cross contamination and cross infections. The most effective form of bactericidal product there is for MRSA and VRE.