Impact of the Environment on Infections in Healthcare Facilities

by Anjali Joseph, Ph.D.

Published by The Center for Health Design, 2006

ABSTRACT

Objective: To examine how nosocomial infections spread among hospitalized patients via environmental routes and whether the design of the hospital plays a part in preventing the incidence and spread of infections.

Methods: Literature review of peer reviewed journal articles and research reports published in medicine, infection control, architecture, and epidemiology publications. Interview with industry experts.

Key Findings

Hospital-acquired infections, or nosocomial infections, are one of the leading causes of death in the United States and typically affect patients whose immune systems are compromised. Nosocomial infections are transmitted in hospitals through three main environmental routes — air, surface contact and water. Airborne infections are spread when dust and pathogens are released during hospital renovation and construction activities and due to contamination and malfunction of the hospital ventilation system. Providing clean filtered air and effectively con- trolling indoor air pollution through ventilation are two key aspects of maintaining good air quality. HEPA filters are highly effective in preventing airborne infections from entering the hos- pital environment. Most nosocomial infections are transmitted through contact with the hands of nurses and physicians, and poor handwashing compliance poses a serious problem in this regard. There is some evidence that environmental support for handwashing — by providing numerous, conveniently located alcohol-rub dispensers or washing sinks — can increase compli- ance. Single-bed rooms are strongly recommended from an infection-control perspective—it is easier to isolate infectious pathogens and disinfect single-bed rooms than multi-occupancy rooms once a patient has been discharged. Waterborne infections spread through direct contact (e.g., for hydrotherapy), ingestion of contaminated water, indirect contact, and inhalation of aerosols dispersed from water sources. Regular cleaning, maintenance, and testing of water sys- tems and point-of-use fixtures is important for preventing the spread of waterborne infections such as Legionnaires’ disease.

Conclusions

Careful consideration of environmental routes for transmission of infection — air, surface and water -- can help in redcing nosocomial infection rates in hospitals.