Disinfection of Bloodborne Pathogens
Paula Grahs RN, BSN, CNOR
For the disinfection of bloodborne pathogens knowledge of the basic principles of disinfection is needed to prevent the risk of disease transmission via inanimate objects. It is the responsibility of all personnel involved with handling these objects to understand these principles. Studies have shown that bloodborne pathogens (HIV, HBV, and HCV) are inactivated rapidly after being exposed to commonly-used chemical disinfectants at concentrations that are much lower than those used in practice.4,7
Disinfection is the process that eliminates many or all pathogenic microorganisms with the exception of bacterial spores from inanimate objects.2 Disinfection is affected by a number of factors:
Table 2 correlates the three device classifications with Spaulding's process classifications and the EPA's product classification.
Universal Precautions with the appropriate personnel protective equipment should always be used when dealing with contaminated items during cleaning and decontamination procedures. Items must be thoroughly cleaned before being disinfected because dirt, blood, mucous, and tissue may interfere with the action of the disinfectant.
The disinfectant in sufficient concentrations at the correct temperature must remain in contact with the surfaces for a specific period of time to allow penetration of all the microbial cell walls and deactivation. The concentration, temperature, and exposure times are different for each disinfectant and the manufacturer's directions for use must be followed carefully.
Chemical disinfectants should not be mixed with each other or with detergents, since this may inactivate their disinfecting properties or create noxious fumes.
If air is entrapped under or within an item, the disinfectant cannot completely contact all the surfaces. Items should be dry to prevent dilution of the disinfectant. When indicated, it is essential that the disinfectant be thoroughly rinsed from items before the items are used. Be sure that you always follow the manufacturer's recommendations when using chemical disinfectants.
Personnel should take precautions to avoid direct contact with chemical disinfectants and they should always be used in well-ventilated areas. Material Safety Data Sheets (MSDS) should be readily available in the event of exposure.
Some ask if we should sterilize or high-level disinfect semi-critical medical devices contaminated by blood from patients infected with a bloodborne disease. The CDC recommendation for high level disinfection is appropriate because studies have shown the effectiveness of high level disinfectants to inactivate these and other pathogens that may contaminate semi-critical devices.2 To sterilize these items when used on certain infectious patients may lead to a "double standard" of patient care and is inconsistent with the principles of universal precautions when equipment used on patients with known specific infectious diseases is sterilized, but the same equipment is high-level disinfected for other patients. Sterilization should not be performed in the belief that it is providing a greater margin of safety. Standard sterilization and disinfection procedures for patient care equipment are adequate to sterilize or disinfect instruments or devices contaminated with blood or other body fluids from persons infected with bloodborne pathogens. No changes in procedures for cleaning, disinfecting, or sterilizing need to be made.2
Chemical germicides that are EPA approved for use as "hospital disinfectants" and that are tuberculocidal/virucidal or have HIV/human HBV claims (OSHA, 1997, 1999) when used at recommended dilutions and contact times can be used to decontaminate spills of blood. Extraordinary attempts to disinfect walls and floors or other environmental surfaces are not necessary. However, cleaning and removal of soil should be done on a routine basis.4,7
The importance of proper cleaning and disinfection cannot be stressed enough and it is essential in protecting patients and personnel from potentially harmful microorganisms. When considering disinfection of bloodborne pathogens, the basic principles of disinfection apply. Careful attention to the process of cleaning and disinfection will provide the safety that is needed when an item is being reused in caring for patients.
Paula Grahs, RN, BSN, CNOR is Central Supply Manager at St. Luke's Hospital in Cedar Rapids, Iowa.
Rutala WA. "APIC Guidelines for Selection and Use of Disinfectants. American Journal of Infection Control 1996; 24:315. OSHA, 1997, 1999.
For a complete list of references please visit our web site at www.infectioncontroltoday.com.
NONLIPID OR SMALL VIRUSES
LIPID OR MEDIUM-SIZED VIRUSES
Herpes simplex virus
Human immunodeficiency virus
Descending order of resistance to germicidal chemicals. This hierarchy considers broad classifications of microbial categories. It is considered a rough guide to general susceptibility of microorganisms to disinfectants.
Rutala WA. APIC Guidelines for Selection and Use of Disinfectants. American Journal of Infection Control 1996; 24: 314.
|Device classification||Device (examples)||Spaulding process classification||EPA product classification|
|Critical (enters sterile tissue or vascular system||Implants, scalpels, needles, other surgical instruments, etc.||Sterilization - sporicidal chemical prolonged contact||Sterilant/disinfectant|
|Semicritical (touches mucous membranes [except dental])||Flexible endoscopes, laryngoscopes, endotracheal tubes, and other similar instruments||High-level disinfection- Sporicidal chemical; short contact||Sterilant/disinfectant|
|Noncritical (touches intact skin)||Thermometers, hydrotherapy tanks||Intermediate-level disinfection||Hospital disinfectant with label claim for tuberculocidal activity|
|Stethoscopes, tabletops, bedpans, etc.||Low-level disinfection||Hospital disinfectant without label claim for tuberculocidal activity|
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