ABSTRACT
The disinfection of hospital equipment and surfaces is essential for interrupting aerobiological pathways. The primary sources of airborne nosocomial pathogens are humans and the environment while the intermediate pathways of airborne infections can include surfaces, equipment, and hands. Bacteria shed from humans will tend to settle downward over time and accumulate on horizontal surfaces such as —oors, tables, bed sheets, etc. Individual viruses (virions) or clumps of viruses may remain suspended in air indeŸnitely, but viruses that are attached to dust particles or droplet nuclei will tend to settle downward over time. Environmental microbes like Aspergillus spores may enter a hospital through doorways, leaky Ÿlters, or windows, or may be brought inside on shoes and clothing, and they will also tend to settle toward the —oor. Aspergillus spores are often or occasionally detected in operating rooms, which have Ÿlters that are impermeable to fungal spores, and so it must be inferred that spores are traveling through hospital hallways or being carried by personnel from the outside to the ORs. Floors may well be a pathway to the OR for spores and other environmental bacteria, and microbes resting on horizontal surfaces such as —oors and carpets can become re-aerosolized through activity and trafŸc (Ayliffe et al. 1967). Once re-aerosolized, these microbes may present an inhalation hazard or they may settle on wounds, catheters, and other equipment and result in infections. Interrupting the aerobiological pathway by disinfecting —oors and other hospital surfaces can break the chain of causation of airborne infections and so the disinfection of hospital rooms, equipment, and surfaces can play a direct role in interdicting airborne pathogens.
