In simpler settings suitable PPE, ventilation, good hygiene practices and regular cleaning may be enough. In higher-risk settings such as infectious disease wards, aged care homes where residents are especially vulnerable, and during outbreaks consider increased hand hygiene, more frequent cleaning and disinfection, improved ventilation (surgical plume evacuators, HEPA filters), negative pressure rooms, signage on rooms, physical distancing, testing visitors, isolating infected people in isolation rooms or by cohorting, and portable medical tents. Seek and monitor authoritative advice, especially during outbreaks or emerging hazards. Review controls when new information arises, such as a new virus or strain or new vaccine. In the norovirus case, outbreak measures applied to nursing staff but cleaning staff and cooks had no training or PPE, hand hygiene and routine cleaning of dining areas were poor, and the virus spread to six more people including three workers, so later outbreak plans trained all roles and increased cleaning of frequently touched surfaces.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.