Guideline for isolation precautions in hospitals. Part I. Evolution of isolation practices

The Guideline for Isolation Precautions in Hospital was revised to meet the following objectives: (1) to be epidemiologically sound, (2) to recognize the importance of all body fluids, secretions, and excretions in the transmission of nosocomial pathogens, (3) to contain adequate precautions for infections transmitted by the airborne, droplet, and contact routes of transmission, (4) to be as simple and user friendly as possible, and (5) to use new terms to avoid confusion with existing infection control and isolation systems. The revised guideline contains two tiers of precautions. In the first and most important tier are those precautions designed for the care of all patients in hospitals regardless of their diagnosis or presumed infection status. Implementation of these 'Standard Precautions' is the primary strategy for successful nosocomial infection control. In the second tier are precautions designed only for the care of specified patients. These additional 'Transmission-based Precautions' are used for patients known or suspected to be infected or colonized with epidemiologically important pathogens that can be transmitted by airborne or droplet transmission or by contact with dry skin or contaminated surfaces. Standard Precautions synthesize the major features of Universal (Blood and Body Fluid) Precautions (designed to reduce the risk of transmission of blood-borne pathogens) and Body Substance Isolation (designed to reduce the risk of transmission of pathogens from moist body substances). Standard precautions apply to (1) blood, (2) all body fluids, secretions, and excretions except sweat regardless of whether they contain visible blood, (3) nonintact skin, and (4) mucous membranes. Standard Precautions are designed to reduce the risk of transmission of microorganisms from both recognized and unrecognized sources of infection in hospitals. Transmission-based Precautions are designed for patients known or suspected to be infected or colonized with highly transmissible or epidemiologically important pathogens for which additional precautions beyond Standard Precautions are needed to interrupt transmission in hospitals. There are three types of Transmission-based Precautions: Airborne Precautions, Droplet Precautions, and Contact Precautions. They may be combined together for diseases that have multiple routes of transmission. When used either singularly or in combination, they are to be used in addition to Standard Precautions. The revised guideline also lists specific clinical syndromes or conditions in both adult and pediatric patients that are highly suspicious for infection and identifies appropriate. Transmission- based Precautions to use on an empiric, temporary basis until a diagnosis can be made; these empiric, temporary precautions are also to be used in addition to Standard Precautions.