Guidelines for Environmental Infection Control in Health-Care Facilities

Prepared by
Lynne Sehulster, Ph.D. 1
Raymond Y.W. Chinn, M.D. 2
1 Division of Healthcare Quality Promotion
National Center for Infectious Diseases
2 HICPAC member
Sharp Memorial Hospital
San Diego, California The material in this report originated in the National Center for Infectious Diseases, James M. Hughes, M.D., Director; and the Division of Healthcare Quality Promotion, Steven L. Solomon, M.D., Acting Director.

Summary

The health-care facility environment is rarely implicated in disease transmission, except among patients who are immunocompromised. Nonetheless, inadvertent exposures to environmental pathogens (e.g., Aspergillus spp. and Legionella spp.) or airborne pathogens (e.g., Mycobacterium tuberculosis and varicella-zoster virus) can result in adverse patient outcomes and cause illness among health-care workers. Environmental infection-control strategies and engineering controls can effectively prevent these infections. The incidence of health-care--associated infections and pseudo-outbreaks can be minimized by 1) appropriate use of cleaners and disinfectants; 2) appropriate maintenance of medical equipment (e.g., automated endoscope reprocessors or hydrotherapy equipment); 3) adherence to water-quality standards for hemodialysis, and to ventilation standards for specialized care environments (e.g., airborne infection isolation rooms, protective environments, or operating rooms); and 4) prompt management of water intrusion into the facility. Routine environmental sampling is not usually advised, except for water quality determinations in hemodialysis settings and other situations where sampling is directed by epidemiologic principles, and results can be applied directly to infection-control decisions. This report reviews previous guidelines and strategies for preventing environment-associated infections in health-care facilities and offers recommendations. These include 1) evidence-based recommendations supported by studies; 2) requirements of federal agencies (e.g., Food and Drug Administration, U.S. Environmental Protection Agency, U.S. Department of Labor, Occupational Safety and Health Administration, and U.S. Department of Justice); 3) guidelines and standards from building and equipment professional organizations (e.g., American Institute of Architects, Association for the Advancement of Medical Instrumentation, and American Society of Heating, Refrigeration, and Air-Conditioning Engineers); 4) recommendations derived from scientific theory or rationale; and 5) experienced opinions based upon infection-control and engineering practices. The report also suggests a series of performance measurements as a means to evaluate infection-control efforts.

Introduction

Parameters of the Report

Performance Measurements

  1. Document whether infection-control personnel are actively involved in all phases of a health-care facility's demolition, construction, and renovation. Activities should include performing a risk assessment of the necessary types of construction barriers, and daily monitoring and documenting of the presence of negative airflow within the construction zone or renovation area.
  2. Monitor and document daily the negative airflow in AII rooms and positive airflow in PE rooms, especially when patients are in these rooms.
  3. Perform assays at least once a month by using standard quantitative methods for endotoxin in water used to reprocess hemodialyzers, and for heterotrophic and mesophilic bacteria in water used to prepare dialysate and for hemodialyzer reprocessing.
  4. Evaluate possible environmental sources (e.g., water, laboratory solutions, or reagents) of specimen contamination when nontuberculous mycobacteria (NTM) of unlikely clinical importance are isolated from clinical cultures. If environmental contamination is found, eliminate the probable mechanisms.
  5. Document policies to identify and respond to water damage. Such policies should result in either repair and drying of wet structural or porous materials within 72 hours, or removal of the wet material if drying is unlikely within 72 hours.

Updates to Previous Recommendations

Contributors to this report reviewed primarily English-language manuscripts identified from reference searches using the National Library of Medicine's MEDLINE, bibliographies of published articles, and infection-control textbooks. All the recommendations may not reflect the opinions of all reviewers. This report updates the following published guidelines and recommendations: CDC. Guideline for handwashing and hospital environmental control. MMWR 1998;37(No. 24). Replaces sections on microbiologic sampling, laundry, infective waste, and housekeeping. Tablan OC, Anderson LJ, Arden NH, et al., Hospital Infection Control Practices Advisory Committee. Guideline for prevention of nosocomial pneumonia. Infect Control Hosp Epidemiol 1994;15:587--627. Updates and expands environmental infection-control information for aspergillosis and Legionnaires disease; online version incorporates Appendices B, C, and D addressing environmental control and detection of Legionella spp. CDC. Guidelines for preventing the transmission of mycobacterium tuberculosis in health-care facilities. MMWR 1994;43(No. RR13). Provides supplemental information on engineering controls. CDC. Recommendations for preventing the spread of vancomycin resistance: recommendations of the Hospital Infection Control Practices Advisory Committee (HICPAC). MMWR 1995;44(No. RR12). Supplements environmental infection-control information from the section, Hospitals with Endemic VRE or Continued VRE Transmission. Garner JS, Hospital Infection Control Practices Advisory Committee. Guideline for isolation precautions in hospitals. Infect Control Hosp Epidemiol 1996;17:53--80. Supplements and updates topics in Part II --- Recommendations for Isolation Precautions in Hospitals (linen and laundry, routine and terminal cleaning, airborne precautions). Mangram AJ, Horan TC, Pearson ML, Silver LC, Jarvis WR, Hospital Infection Control Practices Advisory Committee. Guideline for prevention of surgical site infection. Infect Control Hosp Epidemiol 1999;4:250--78. Updates operating room ventilation and surface cleaning/disinfection recommendations from the section, Intraoperative Issues: Operating Room Environment. U.S. Public Health Service, Infectious Diseases Society of America, Prevention of Opportunistic Infections Working Group. USPHS/IDSA guidelines for the prevention of opportunistic infections in persons infected with human immunodeficiency virus. Infect Dis Obstet Gynecol 2002; 10:3--64. Supplements information regarding patient interaction with pets and animals in the home. CDC, Infectious Diseases Society of America, American Society of Blood and Marrow Transplantation. Guidelines for preventing opportunistic infections among hematopoietic stem cell transplant recipients. Cytotherapy 2001;3:41--54. Supplements and updates the section, Hospital Infection Control.

Key Terms

Airborne infection isolation (AII) refers to the isolation of patients infected with organisms spread via airborne droplet nuclei <5 µm in diameter. This isolation area receives numerous air changes per hour (ACH) ( >12 ACH for new construction as of 2001; > 6 ACH for construction before 2001), and is under negative pressure, such that the direction of the air flow is from the outside adjacent space (e.g., the corridor) into the room. The air in an AII room is preferably exhausted to the outside, but may be recirculated provided that the return air is filtered through a high-efficiency particulate air (HEPA) filter. The use of personal respiratory protection is also indicated for persons entering these rooms when caring for TB or smallpox patients and for staff who lack immunity to airborne viral diseases (e.g., measles or varicella zoster virus [VZV] infection). Protective environment (PE) is a specialized patient-care area, usually in a hospital, with a positive air flow relative to the corridor (i.e., air flows from the room to the outside adjacent space). The combination of HEPA filtration, high numbers of air changes per hour ( > 12 ACH), and minimal leakage of air into the room creates an environment that can safely accommodate patients who have undergone allogeneic hematopoietic stem cell transplant (HSCT). Immunocompromised patients are those patients whose immune mechanisms are deficient because of immunologic disorders (e.g., human immunodeficiency virus [HIV] infection or congenital immune deficiency syndrome), chronic diseases (e.g., diabetes, cancer, emphysema, or cardiac failure), or immunosuppressive therapy (e.g., radiation, cytotoxic chemotherapy, anti-rejection medication, or steroids). Immunocompromised patients who are identified as high-risk patients have the greatest risk of infection caused by airborne or waterborne microorganisms. Patients in this subset include persons who are severely neutropenic for prolonged periods of time (i.e., an absolute neutrophil count [ANC] of < 500 cells/mL), allogeneic HSCT patients, and those who have received the most intensive chemotherapy (e.g., childhood acute myelogenous leukemia patients).

Abbreviations

AAMI Association for the Advancement of Medical Instrumentation ACH air changes per hour AER automated endoscope reprocessor AHJ authority having jurisdiction AIA American Institute of Architects AII airborne infection isolation ANSI American National Standards Institute ASHRAE American Society of Heating, Refrigeration, and Air-Conditioning Engineers BMBL Biosafety in Microbiological and Biomedical Laboratories (CDC/National Institutes of Health) CFR Code of Federal Regulations CJD Creutzfeldt-Jakob disease CPL compliance document (OSHA) DFA direct fluorescence assay DHHS U.S. Department of Health and Human Services DOT U.S. Department of Transportation EC environment of care EPA U. S. Environmental Protection Agency FDA U.S. Food and Drug Administration HBV hepatitis B virus HEPA high efficiency particulate air HIV human immunodeficiency virus HSCT hematopoietic stem cell transplant HVAC heating, ventilation, air conditioning ICRA infection-control risk assessment JCAHO Joint Commission on Accreditation of Healthcare Organizations NaOH sodium hydroxide NTM nontuberculous mycobacteria OSHA Occupational Safety and Health Administration PE protective environment PPE personal protective equipment TB tuberculosis USC United States Code USDA U.S. Department of Agriculture UV ultraviolet UVGI ultraviolet germicidal irradiation VHF viral hemorrhagic fever VRE vancomycin-resistant Enterococcus VRSA vancomycin-resistant Staphylococcus aureus VZV varicella zoster virus

Recommendations for Environmental Infection Control in Health-Care Facilities

Rationale for Recommendations

As in previous CDC guidelines, each recommendation is categorized on the basis of existing scientific data, theoretic rationale, applicability, and possible economic effect. The recommendations are evidence-based wherever possible. However, certain recommendations are derived from empiric infection-control or engineering principles, theoretic rationale, or from experience gained from events that cannot be readily studied (e.g., floods). The HICPAC system for categorizing recommendations has been modified to include a category for engineering standards and actions required by state or federal regulations. Guidelines and standards published by the AIA, American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE), and the Association for the Advancement of Medical Instrumentation (AAMI) form the basis of certain recommendations. These standards reflect a consensus of expert opinions and extensive consultation with agencies of the U.S. Department of Health and Human Services. Compliance with these standards is usually voluntary. However, state and federal governments often adopt these standards as regulations. For example, the standards from AIA regarding construction and design of new or renovated health-care facilities, have been adopted by reference by >40 states. Certain recommendations have two category ratings (e.g., Categories IA and IC or Categories IB and IC), indicating the recommendation is evidence-based as well as a standard or regulation.

Rating Categories

Recommendations are rated according to the following categories: Category IA. Strongly recommended for implementation and strongly supported by well-designed experimental, clinical, or epidemiologic studies. Category IB. Strongly recommended for implementation and supported by certain experimental, clinical, or epidemiologic studies and a strong theoretic rationale. Category IC. Required by state or federal regulation, or representing an established association standard. (Note: Abbreviations for governing agencies and regulatory citations are listed where appropriate. Recommendations from regulations adopted at state levels are also noted. Recommendations from AIA guidelines cite the appropriate sections of the standards.) Category II. Suggested for implementation and supported by suggestive clinical or epidemiologic studies, or a theoretic rationale. Unresolved issue. No recommendation is offered. No consensus or insufficient evidence exists regarding efficacy.

Recommendations --- Air

  1. Use AIA guidelines as minimum standards where state or local regulations are not in place for design and construction of ventilation systems in new or renovated health-care facilities. Ensure that existing structures continue to meet the specifications in effect at the time of construction ( 1 ). Category IC (AIA: 1.1.A, 5.4)
  2. Monitor ventilation systems in accordance with engineers' and manufacturers' recommendations to ensure preventive engineering, optimal performance for removal of particulates, and elimination of excess moisture ( 1--8 ). Category IB, IC (AIA: 7.2, 7.31.D, 8.31.D, 9.31.D, 10.31.D, 11.31.D, Environmental Protection Agency [EPA] guidance)

1. Ensure that heating, ventilation, air conditioning (HVAC) filters are properly installed and maintained to prevent air leakages and dust overloads ( 2,4,6,9 ). Category IB
2. Monitor areas with special ventilation requirements (e.g., AII or PE) for ACH, filtration, and pressure differentials ( 1,7,8,10--26 ). Category IB, IC (AIA: 7.2.C7, 7.2.D6)

a. Develop and implement a maintenance schedule for ACH, pressure differentials, and filtration efficiencies by using facility-specific data as part of the multidisciplinary risk
assessment. Take into account the age and reliability of the system.
b. Document these parameters, especially the pressure differentials.

3. Engineer humidity controls into the HVAC system and monitor the controls to ensure adequate moisture removal ( 1 ). Category IC (AIA: 7.31.D9)

a. Locate duct humidifiers upstream from the final filters.
b. Incorporate a water-removal mechanism into the system.
c. Locate all duct takeoffs sufficiently downstream from the humidifier so that moisture is completely absorbed.

4. Incorporate steam humidifiers, if possible, to reduce potential for microbial proliferation within the system, and avoid use of cool-mist humidifiers. Category II
5. Ensure that air intakes and exhaust outlets are located properly in construction of new facilities and renovation of existing facilities ( 1,27 ). Category IC (AIA: 7.31.D3, 8.31.D3,
9.31.D3, 10.31.D3, 11.31.D3)

a. Locate exhaust outlets >25 ft from air-intake systems.
b. Locate outdoor air intakes > 6 ft above ground or > 3 ft above roof level.
c. Locate exhaust outlets from contaminated areas above roof level to minimize recirculation of exhausted air.

6. Maintain air intakes and inspect filters periodically to ensure proper operation ( 1,11--16,27 ). Category IC (AIA: 7.31.D8)
7. Bag dust-filled filters immediately upon removal to prevent dispersion of dust and fungal spores during transport within the facility ( 4,28 ). Category IB

a. Seal or close the bag containing the discarded filter.
b. Discard spent filters as regular solid waste, regardless of the area from which they were removed ( 28 ).

II. Construction, Renovation, Remediation, Repair, and Demolition

  1. Establish a multidisciplinary team that includes infection-control staff to coordinate demolition, construction, and renovation projects and consider proactive preventive measures at the inception; produce and maintain summary statements of the team's activities ( 1,9,11--16,38,48--51 ). Category IB, IC (AIA: 5.1)
  2. Educate both the construction team and health-care staff in immunocompromised patient-care areas regarding the airborne infection risks associated with construction projects, dispersal of fungal spores during such activities, and methods to control the dissemination of fungal spores ( 11--16,27,50,52--56 ). Category IB
  3. Incorporate mandatory adherence agreements for infection control into construction contracts, with penalties for noncompliance and mechanisms to ensure timely correction of problems ( 1,11,13--16,27,50 ). Category IC (AIA: 5.1)
  4. Establish and maintain surveillance for airborne environmental disease (e.g., aspergillosis) as appropriate during construction, renovation, repair, and demolition activities to ensure the health and safety of immunocompromised patients ( 27,57--59 ). Category IB

1. Before the project gets under way, perform an ICRA to define the scope of the activity and the need for barrier measures ( 1,11,13--16,48--51,60 ). Category IB, IC (AIA: 5.1)

a. Determine if immunocompromised patients may be at risk for exposure to fungal spores from dust generated during the project ( 13--16,48,51 ).
b. Develop a contingency plan to prevent such exposures ( 13--16,48,51 ).

2. Implement infection-control measures for external demolition and construction activities ( 11,13--16,50,61,62 ). Category IB

a. Determine if the facility can operate temporarily on recirculated air; if feasible, seal off adjacent air intakes.
b. If this is not possible or practical, check the low-efficiency (roughing) filter banks frequently and replace as needed to avoid buildup of particulates.
c. Seal windows and reduce wherever possible other sources of outside air intrusion (e.g., open doors in stairwells and corridors), especially in PE areas.

3. Avoid damaging the underground water system (i.e., buried pipes) to prevent soil and dust contamination of the water ( 1,63 ). Category IB, IC (AIA: 5.1)
4. Implement infection-control measures for internal construction activities ( 1,11,13--16,48-- 50,64 ). Category IB, IC (AIA: 5.1, 5.2)

a. Construct barriers to prevent dust from construction areas from entering patient-care areas; ensure that barriers are impermeable to fungal spores and in compliance with local fire
codes ( 1,45,48,49,55,64--66 ).
b. Seal off and block return air vents if rigid barriers are used for containment ( 1,16,50 ).
c. Implement dust-control measures on surfaces and divert pedestrian traffic away from work zones ( 1,48,49,64 ).
d. Relocate patients whose rooms are adjacent to work zones, depending on their immune status, the scope of the project, the potential for generation of dust or water aerosols, and
the methods used to control these aerosols ( 1,64,65 ).

5. Perform those engineering and work-site related infection-control measures as needed for internal construction, repairs, and renovations ( 1,48,49,51,64,66 ). Category IB, IC (AIA:
5.1, 5.2)

III. Infection Control and Ventilation Requirements for PE rooms

  1. Minimize exposures of severely immunocompromised patients (e.g., solid-organ transplant patients or allogeneic neutropenic patients) to activities that might cause aerosolization of fungal spores (e.g., vacuuming or disruption of ceiling tiles) ( 37,48,51,73 ). Category IB
  2. Minimize the length of time that immunocompromised patients in PE are outside their rooms for diagnostic procedures and other activities ( 37,62 ). Category IB
  3. Provide respiratory protection for severely immunocompromised patients when they must leave PE for diagnostic procedures and other activities; consult the most recent revision of CDC's Guideline for Prevention of Health-Care--Associated Pneumonia for information regarding the appropriate type of respiratory protection. ( 27,37 ). Category II
  4. Incorporate ventilation engineering specifications and dust-controlling processes into the planning and construction of new PE units (Figure 1). Category IB, IC

IV. Infection-Control and Ventilation Requirements for AII Rooms

    Incorporate certain specifications into the planning and construction or renovation of AII units ( 1,34,100,101,104 ) (Figure 3). Category IB, IC

1. Use AII rooms for patients with or suspected of having an airborne infection who also require cough-inducing procedures, or use an enclosed booth that is engineered to provide 1)
> 12 ACH; 2) air supply and exhaust rate sufficient to maintain a 2.5 Pa (0.01-inch water gauge) negative pressure difference with respect to all surrounding spaces with an exhaust
rate of > 50 ft 3 /min; and 3) air exhausted directly outside away from air intakes and traffic or exhausted after HEPA filtration before recirculation ( 1,34,105--107 ). Category IB, IC
(AIA: 7.15.E, 7.31.D23, 9.10, Table 7.2)
2. Although airborne spread of viral hemorrhagic fever (VHF) has not been documented in a health-care setting, prudence dictates placing a VHF patient in an AII room, preferably
with an anteroom, to reduce the risk of occupational exposure to aerosolized infectious material in blood, vomitus, liquid stool, and respiratory secretions present in large amounts
during the end stage of a patient's illness ( 108--110 ). Category II

a. If an anteroom is not available, use portable, industrial-grade HEPA filters in the patient's room to provide additional ACH equivalents for removing airborne particulates.
b. Ensure that health-care workers wear face shields or goggles with appropriate respirators when entering the rooms of VHF patients with prominent cough, vomiting, diarrhea, or
hemorrhage ( 109 ).

V. Infection-Control and Ventilation Requirements for Operating Rooms

    Implement environmental infection-control and ventilation measures for operating rooms.

VI. Other Potential Infectious Aerosol Hazards in Health-Care Facilities

  1. In settings where surgical lasers are used, wear appropriate personal protective equipment (PPE), including N95 or N100 respirators, to minimize exposure to laser plumes ( 129,135,136 ). Category IC (OSHA; 29 CFR 1910.134,139)
  2. Use central wall suction units with in-line filters to evacuate minimal laser plumes ( 135--138 ). Category II
  3. Use a mechanical smoke evacuation system with a high-efficiency filter to manage the generation of large amounts of laser plume, when ablating tissue infected with human papilloma virus (HPV) or performing procedures on a patient with extrapulmonary TB ( 34,136,137,139--141 ). Category II

Recommendations --- Water

I. Controlling the Spread of Waterborne Microorganisms

  1. Practice hand hygiene to prevent the hand transfer of waterborne pathogens, and use barrier precautions (e.g., gloves) as defined by other guidelines ( 36,142--146 ). Category IA
  2. Eliminate contaminated water or fluid environmental reservoirs (e.g., in equipment or solutions) wherever possible ( 142,147 ). Category IB
  3. Clean and disinfect sinks and wash basins on a regular basis by using an EPA-registered product as set by facility policies. Category II
  4. Evaluate for possible environmental sources (e.g., potable water) of specimen contamination when waterborne microorganisms (e.g., NTM) of unlikely clinical importance are isolated from clinical cultures (e.g., specimens collected aseptically from sterile sites or, if postprocedural, colonization after use of tap water in patient care) ( 148--151 ). Category IB
  5. Avoid placing decorative fountains and fish tanks in patient-care areas; ensure disinfection and fountain maintenance if decorative fountains are used in public areas of the health-care facility ( 152 ). Category IB

II. Routine Prevention of Waterborne Microbial Contamination Within the Distribution System

  1. Maintain hot water temperature at the return at the highest temperature allowable by state regulations or codes, preferably > 124 º F ( > 51 º C), and maintain cold water temperature at
  2. If the hot water temperature can be maintained at > 124 º F ( > 51 º C), explore engineering options (e.g., installing preset thermostatic valves in point-of-use fixtures) to help minimize the risk of scalding ( 153) . Category II
  3. When state regulations or codes do not allow hot water temperatures above the range of 105 º F--120 º F (40.6 º C--49 º C) for hospitals or 95 º F--110 º F (35 º C--43.3 º C) for nursing care facilities or when buildings cannot be retrofitted for thermostatic mixing valves, follow either of these alternative preventive measures to minimize the growth of Legionella spp. in water systems. Category II

III. Remediation Strategies for Distribution System Repair or Emergencies

  1. Whenever possible, disconnect the ice machine before planned water disruptions. Category II
  2. Prepare a contingency plan to estimate water demands for the entire facility in advance of significant water disruptions (i.e., those expected to result in extensive and heavy microbial or chemical contamination of the potable water), sewage intrusion, or flooding ( 45,156 ). Category IC (JCAHO: EC 1.4)
  3. When a significant water disruption or an emergency occurs, adhere to any advisory to boil water issued by the municipal water utility ( 157 ). Category IB, IC (Municipal order)

1. Decontaminate the system when the fewest occupants are present in the building (e.g., nights or weekends) ( 27,153 ). Category IC (ASHRAE: 12:2000)
2. If using high-temperature decontamination, raise the hot-water temperature to 160 º F--170 º F (71 º C--77 º C) and maintain that level while progressively flushing each outlet around the
system for > 5 minutes ( 27,153 ). Category IC (ASHRAE: 12:2000)
3. If using chlorination, add enough chlorine, preferably overnight, to achieve a free chlorine residual of > 2 mg/L ( > 2 ppm) throughout the system ( 153 ). Category IC (ASHRAE:
12:2000)

a. Flush each outlet until chlorine odor is detected.
b. Maintain the elevated chlorine concentration in the system for > 2 (but < 24 hrs).

IV. Additional Engineering Measures as Indicated by Epidemiologic Investigation for Controlling Waterborne, Health-Care--Associated Legionnaires Disease

  1. When using a pulse or one-time decontamination method, superheat the water by flushing each outlet for > 5 minutes with water at 160 º F--170 º F (71 º C--77 º C) or hyperchlorinate the system by flushing all outlets for > 5 minutes with water containing > 2 mg/L ( > 2 ppm) free residual chlorine using a chlorine-based product registered by the EPA for water treatment (e.g., sodium hypochlorite [chlorine bleach]) ( 153,155,161--164 ). Category IB
  2. After a pulse treatment, maintain both the heated water temperature at the return and the cold water temperature per the recommendation (Water: II A) wherever practical and permitted by state codes, or chlorinate heated water to achieve 1--2 mg/L (1--2 ppm) free residual chlorine at the tap by using a chlorine-based product registered by the EPA for water treatment (e.g., sodium hypochlorite [bleach]) ( 153,165--169 ). Category IC (States; ASHRAE: 12:2000)
  3. Explore engineering or educational options (e.g., install preset thermostatic mixing valves in point-of-use fixtures or post warning signs at each outlet) to minimize the risk of scalding for patients, visitors, and staff. Category II
  4. No recommendation is offered for treating water in the facility's distribution system with chlorine dioxide, heavy-metal ions (e.g., copper or silver), monochloramines, ozone, or UV light ( 170--188 ). Unresolved issue

V. General Infection-Control Strategies for Preventing Legionnaires Disease

  1. Conduct an infection-control risk assessment of the facility to determine if patients at risk or severely immunocompromised patients are present ( 27,189,190 ). Category IB
  2. Implement general strategies for detecting and preventing Legionnaires disease in facilities that do not provide care for severely immunocompromised patients (i.e., facilities that do not have HSCT or solid-organ transplant programs) (see Appendix) ( 27,189,190 ). Category IB

VI. Preventing Legionnaires Disease in Protective Environments and Transplant Units

    When implementing strategies for preventing Legionnaires disease among severely immunocompromised patients housed in facilities with HSCT or solid-organ transplant programs, incorporate these specific surveillance and epidemiologic measures in addition to the steps outlined previously (see Appendix).

VII. Cooling Towers and Evaporative Condensers

  1. When planning construction of new health-care facilities, locate cooling towers so that the drift is directed away from the air-intake system, and design the towers to minimize the volume of aerosol drift ( 153,203,221 ). Category IC (ASHRAE 12-2000)
  2. Implement infection-control procedures for operational cooling towers ( 153,203,222 ). Category IC (ASHRAE 12-2000)

VIII. Dialysis Water Quality and Dialysate

  1. Adhere to current AAMI standards for quality-assurance performance of devices and equipment used to treat, store, and distribute water in hemodialysis centers (both acute and maintenance [chronic] settings) and for the preparation of concentrates and dialysate ( 224--235 ). Category IA, IC (AAMI: American National Standards Institute [ANSI]/AAMI RD5:1992, ANSI/AAMI RD47:1993)
  2. No recommendation is offered regarding whether more stringent requirements for water quality should be imposed in hemofiltration and hemodiafiltration. Unresolved issue
  3. Conduct microbiologic testing specific to water in dialysis settings ( 229,230,236--238 ). Category IA, IC (AAMI: ANSI/AAMI RD5:1992, ANSI/AAMI RD47:1993, RD62:2001)

1. Perform bacteriologic assays of water and dialysis fluids at least once a month and during outbreaks by using standard quantitative methods ( 236--238 ). Category IA, IC (AAMI:
ANSI/AAMI RD62:2001)

a. Assay for heterotrophic, mesophilic bacteria (e.g., Pseudomonas spp).
b. Do not use nutrient-rich media (e.g., blood agar or chocolate agar).

IX. Ice Machines and Ice

  1. Do not handle ice directly by hand, and wash hands before obtaining ice. Category II
  2. Use a smooth-surface ice scoop to dispense ice ( 243,244 ). Category II

X. Hydrotherapy Tanks and Pools

  1. Drain and clean hydrotherapy equipment (e.g., Hubbard tanks, tubs, whirlpools, whirlpool spas, or birthing tanks) after each patient's use, and disinfect equipment surfaces and components by using an EPA-registered product in accordance with the manufacturer's instructions. Category II
  2. In the absence of an EPA-registered product for water treatment, add sodium hypochlorite to the water:

XI. Miscellaneous Medical Equipment Connected to Water Systems

    Clean, disinfect, and maintain AER equipment according to the manufacturer's instructions and relevant scientific literature to prevent inadvertent contamination of endoscopes and bronchoscopes with waterborne microorganisms ( 253--257 ). Category IB

Recommendations ---Environmental Services

I. Cleaning and Disinfecting Strategies for Environmental Surfaces in Patient-Care Areas

  1. Select EPA-registered disinfectants, if available, and use them in accordance with the manufacturer's instructions ( 270--272 ). Category IC (EPA: 7 United States Code [USC] § 136 et seq.)
  2. Do not use high-level disinfectants/liquid chemical sterilants for disinfection of either noncritical instruments and devices or any environmental surfaces; such use is counter to label instructions for these toxic chemicals ( 273--278 ). Category IC (Food and Drug Administration [FDA]: 21 CFR 801.5, 807.87.e)
  3. Follow manufacturers' instructions for cleaning and maintaining noncritical medical equipment. Category II
  4. In the absence of a manufacturer's cleaning instructions, follow certain procedures.

II. Cleaning Spills of Blood and Body Substances

  1. Promptly clean and decontaminate spills of blood or other potentially infectious materials ( 293--300 ). Category IB, IC (OSHA: 29 CFR 1910.1030 § d.4.ii.A)
  2. Follow proper procedures for site decontamination of spills of blood or blood-containing body fluids ( 293--300 ). Category IC (OSHA: 29 CFR 1910.1030 § d.4.ii.A)

III. Carpeting and Cloth Furnishings

  1. Vacuum carpeting in public areas of health-care facilities and in general patient-care areas regularly with well-maintained equipment designed to minimize dust dispersion ( 280 ). Category II
  2. Periodically perform a thorough, deep cleaning of carpeting as determined by facility policy by using a method that minimizes the production of aerosols and leaves little or no residue ( 44 ). Category II
  3. Avoid use of carpeting in high-traffic zones in patient-care areas or where spills are likely (e.g., burn therapy units, operating rooms, laboratories, or intensive care units) ( 44,305,306 ). Category IB
  4. Follow appropriate procedures for managing spills on carpeting.

IV. Flowers and Plants in Patient-Care Areas

  1. Flowers and potted plants need not be restricted from areas for immunocompetent patients ( 308--311 ). Category II
  2. Designate care and maintenance of flowers and potted plants to staff not directly involved with patient care ( 309 ). Category II
  3. If plant or flower care by patient-care staff is unavoidable, instruct the staff to wear gloves when handling plants and flowers and perform hand hygiene after glove removal ( 309 ). Category II
  4. Do not allow fresh or dried flowers, or potted plants, in patient-care areas for immunosuppressed patients ( 37,51,308,312 ). Category II
  1. Develop pest-control strategies, with emphasis on kitchens, cafeterias, laundries, central sterile supply areas, operating rooms, loading docks, construction activities, and other areas prone to infestations ( 313--315 ). Category II
  2. Install screens on all windows that open to the outside; keep screens in good repair ( 314 ). Category IB
  3. Contract for routine pest control service by a credentialed pest-control specialist who will tailor the application to the needs of a health-care facility ( 315 ). Category II
  4. Place laboratory specimens (e.g., fixed sputum smears) in covered containers for overnight storage ( 316,317 ). Category II

VI. Special Pathogens

  1. Use appropriate hand hygiene, PPE (e.g., gloves), and isolation precautions during cleaning and disinfecting procedures ( 146,274,318,319 ). Category IB
  2. Use standard cleaning and disinfection protocols to control environmental contamination with antibiotic-resistant, gram-positive cocci (e.g., methicillin-resistant Staphylococcus aureus , vancomycin intermediate sensitive Staphylococcus aureus , or vancomycin-resistant Enterococcus [VRE]) ( 318,320--322 ). Category IB

1. In the absence of contamination with central nervous system tissue, extraordinary measures (e.g., use of 2N sodium hydroxide [NaOH] or applying full-strength sodium hypochlorite)
are not needed for routine cleaning or terminal disinfection of a room housing a confirmed or suspected CJD patient ( 273,336 ). Category II
2. After removing gross tissue from the surface, use either 1N NaOH or a sodium hypochlorite solution containing approximately 10,000--20,000 ppm available chlorine (dilutions of
1:5 to 1:3 v/v, respectively, of U.S. household chlorine bleach; contact the manufacturers of commercially available sodium hypochlorite products for advice) to decontaminate
operating room or autopsy surfaces with central nervous system or cerebral spinal fluid contamination from a diagnosed or suspected CJD patient ( 273,337--342 ). Category II

a. The contact time for the chemical used during this process should be 30 min--1 hour ( 339,340,342 ).
b. Blot up the chemical with absorbent material and rinse the treated surface thoroughly with water.
c. Discard the used, absorbent material into appropriate waste containers.

Recommendations ---Environmental Sampling

I. General Information

  1. Do not conduct random, undirected, microbiologic sampling of air, water, and environmental surfaces in health-care facilities ( 270,343 ). Category IB
  2. When indicated, conduct microbiologic sampling as part of an epidemiologic investigation or during assessment of hazardous environmental conditions to detect contamination or verify abatement of a hazard ( 270,343 ). Category IB
  3. Limit microbiologic sampling for quality assurance purposes to 1) biologic monitoring of sterilization processes; 2) monthly cultures of water and dialysate in hemodialysis units; and 3) short-term evaluation of the impact of infection-control measures or changes in infection-control protocols ( 270,343 ). Category IB

II. Air, Water, and Environmental Surface Sampling

  1. When conducting any form of environmental sampling, identify existing comparative standards and fully document departures from standard methods ( 343--347 ). Category II
  2. Select a high-volume air sampling device if anticipated levels of microbial airborne contamination are expected to be low ( 345,346,348,349 ). Category II
  3. Do not use settle plates to quantify the concentration of airborne fungal spores ( 348 ). Category II
  4. When sampling water, choose growth media and incubation conditions that will facilitate recovery of waterborne organisms ( 344 ). Category II
  5. When using a sample/rinse method for sampling an environmental surface, develop and document a procedure for manipulating the swab, gauze, or sponge in a reproducible manner so that results are comparable ( 347 ). Category II
  6. When environmental samples and patient specimens are available for comparison, perform the laboratory analysis on the recovered microorganisms down to the species level at a minimum, and beyond the species level if possible ( 343 ). Category II

Recommendations ---Laundry and Bedding

I. Employer Responsibilities

  1. Employers must launder workers' personal protective garments or uniforms that are contaminated with blood or other potentially infectious materials ( 293 ). Category IC (OSHA: 29 CFR 1910.1030 § d.3.iv)

II. Laundry Facilities and Equipment

  1. Maintain the receiving area for contaminated textiles at negative pressure compared with the clean areas of the laundry in accordance with AIA construction standards in effect during the time of facility construction ( 1,350--352 ). Category IC (AIA: 7.23.B1, B2)
  2. Ensure that laundry areas have handwashing facilities and products and appropriate PPE available for workers ( 1,293 ). Category IC (AIA: 7.23.D4; OSHA: 29 CFR 1910.1030 § d.2.iii)
  3. Use and maintain laundry equipment according to manufacturers' instructions ( 353,354 ). Category II
  4. Do not leave damp textiles or fabrics in machines overnight ( 353 ). Category II
  5. Disinfection of washing and drying machines in residential care is not needed as long as gross soil is removed from items before washing and proper washing and drying procedures are used. Category II

III. Routine Handling of Contaminated Laundry

  1. Handle contaminated textiles and fabrics with minimum agitation to avoid contamination of air, surfaces, and persons ( 36,293,355,356 ). Category IC (OSHA: 29 CFR 1910.1030 § d.4.iv)
  2. Bag or otherwise contain contaminated textiles and fabrics at the point of use ( 293 ). Category IC (OSHA: 29 CFR 1910.1030 § d.4.iv)

IV. Laundry Process

  1. If hot-water laundry cycles are used, wash with detergent in water > 160 º F ( > 71 º C) for > 25 minutes ( 1,270 ). Category IC (AIA: 7.31.E3)
  2. No recommendation is offered regarding a hot-water temperature setting and cycle duration for items laundered in residence-style health-care facilities. Unresolved issue
  3. Follow fabric-care instructions and special laundering requirements for items used in the facility ( 364 ). Category II
  4. Choose chemicals suitable for low-temperature washing at proper use concentration if low-temperature (
  5. Package, transport, and store clean textiles and fabrics by methods that will ensure their cleanliness and protect them from dust and soil during interfacility loading, transport, and unloading ( 270 ). Category II

V. Microbiologic Sampling of Textiles

  1. Do not conduct routine microbiologic sampling of clean textiles ( 270,371 ). Category IB
  2. Use microbiologic sampling during outbreak investigations if epidemiologic evidence indicates a role for health-care textiles and clothing in disease transmission ( 371 ). Category IB

VI. Special Laundry Situations

  1. Use sterilized textiles, surgical drapes, and gowns for situations requiring sterility in patient care ( 114 ). Category IB
  2. Use hygienically clean textiles (i.e., laundered, but not sterilized) in neonatal intensive care units ( 292,372 ). Category IB
  3. Follow manufacturers' recommendations for cleaning fabric products, including those with coated or laminated surfaces. Category II
  4. Do not use dry cleaning for routine laundering in health-care facilities ( 373--375 ). Category II
  5. Use caution when considering use of antimicrobial mattresses, textiles, and clothing as replacements for standard bedding and other fabric items; EPA has not approved public health claims asserting protection against human pathogens for such treated items ( 376 ). Category II
  6. No recommendation is offered regarding using disposable fabrics and textiles versus durable goods. Unresolved issue

VII. Mattresses and Pillows

  1. Keep mattresses dry; discard them if they remain wet or stained, particularly in burn units ( 377--382 ). Category IB
  2. Clean and disinfect mattress covers by using EPA-registered disinfectants that are compatible with the materials to prevent the development of tears, cracks, or holes in the covers ( 377--382 ). Category IB
  3. Maintain the integrity of mattress and pillow covers. Category II

VIII. Air-Fluidized Beds

  1. Follow manufacturers' instructions for air-fluidized bed maintenance and decontamination. Category II
  2. Change the polyester filter sheet at least weekly or as indicated by the manufacturer ( 383--386 ). Category II
  3. Clean and disinfect the polyester filter sheet thoroughly, especially between patients, using an EPA-registered product ( 383--386 ). Category IB
  4. Consult the facility engineer to determine the proper placement of air-fluidized beds in negative-pressure rooms ( 387 ). Category II

Recommendations --- Animals in Health-Care Facilities

I. General Infection-Control Measures for Animal Encounters

  1. Minimize contact with animal saliva, dander, urine, and feces ( 388--390 ). Category II
  2. Practice hand hygiene after any animal contact ( 146,270 ). Category II

II. Animal-Assisted Activities and Resident Animal Programs

  1. Avoid selection of nonhuman primates and reptiles in animal-assisted activities, animal-assisted therapy, or resident animal programs ( 391--393 ). Category IB
  2. Enroll animals that are fully vaccinated for zoonotic diseases and that are healthy, clean, well-groomed, and negative for enteric parasites or otherwise have completed recent anthelmintic treatment under the regular care of a veterinarian ( 391,394 ). Category II
  3. Enroll animals that are trained with the assistance or under the direction of persons who are experienced in this field ( 391 ). Category II
  4. Ensure that animals are controlled by persons trained in providing activities or therapies safely, and who know the animal's health status and behavior traits ( 391,394 ). Category II
  5. Take prompt action when an incident of biting or scratching by an animal occurs during an animal-assisted activity or therapy.

III. Protective Measures for Immunocompromised Patients

  1. Advise patients to avoid contact with animal feces, saliva, urine, or solid litter box material ( 396 ). Category II
  2. Promptly clean and treat scratches, bites, or other wounds that break the skin ( 396 ). Category II
  3. Advise patients to avoid direct or indirect contact with reptiles ( 397 ). Category IB
  4. Conduct a case-by-case assessment to determine if animal-assisted activities or animal-assisted therapy programs are appropriate for immunocompromised patients ( 394 ). Category II
  5. No recommendation is offered regarding permitting pet visits to terminally ill immunocompromised patients outside their PE units. Unresolved issue.

IV. Service Animals

  1. Avoid providing facility access to nonhuman primates and reptiles as service animals ( 393,397 ). Category IB
  2. Allow service animals access to the facility in accordance with the Americans with Disabilities Act of 1990, unless the presence of the animal creates a direct threat to other persons or a fundamental alteration in the nature of services ( 389,398 ). Category IC (U.S. Department of Justice: 28 CFR § 36.302)
  3. When a decision must be made regarding a service animal's access to any particular area of the health-care facility, evaluate the service animal, patient, and health-care situation on a case-by-case basis to determine whether significant risk of harm exists and whether reasonable modifications in policies and procedures will mitigate this risk ( 398 ). Category IC (U.S. Department of Justice: 28 CFR § 36.208)
  4. If a patient must be separated from his or her service animal while in the health-care facility 1) ascertain from the person what arrangements have been made for supervision or care of the animal during this period of separation; and 2) make appropriate arrangements to address the patient's needs in the absence of the service animal. Category II

V. Animals as Patients in Human Health-Care Facilities

    Develop health-care facility policies to address the treatment of animals in human health-care facilities.

VI. Research Animals in Health-Care Facilities

  1. Use animals obtained from quality stock, or quarantine incoming animals to detect zoonotic diseases. Category II
  2. Treat sick animals or remove them from the facility. Category II
  3. Provide prophylactic vaccinations, as available, to animal handlers and contacts at high risk. Category II
  4. Ensure proper ventilation through appropriate facility design and location ( 399 ). Category IC (U.S. Department of Agriculture [USDA]: 7 USC 2131)

Recommendations --- Regulated Medical Wastes

I. Categories of Regulated Medical Waste

  1. Designate the following as major categories of medical waste that require special handling and disposal precautions: 1) microbiology laboratory wastes [e.g., cultures and stocks of microorganisms]; 2) bulk blood, blood products, blood, and bloody body fluid specimens; 3) pathology and anatomy waste; and 4) sharps [e.g., needles and scalpels] ( 270 ). Category II
  2. Consult federal, state, and local regulations to determine if other waste items are considered regulated medical wastes ( 293,402,403 ). Category IC (States; OSHA: 29 CFR 1910.1030 § g.2.1; Department of Transportation [DOT]: 49 CFR 171-180; U.S. Postal Service: CO23.8)

II. Disposal Plan for Regulated Medical Wastes

  1. Develop a plan for the collection, handling, predisposal treatment, and terminal disposal of regulated medical wastes ( 293,404 ). Category IC (States; OSHA: 29 CFR 1910.1030 § g.2.i)
  2. Designate a person or persons as responsible for establishing, monitoring, reviewing, and administering the plan. Category II

III. Handling, Transporting, and Storing Regulated Medical Wastes

  1. Inform personnel involved in handling and disposal of potentially infective waste of possible health and safety hazards; ensure that they are trained in appropriate handling and disposal methods ( 293 ). Category IC (OSHA: 29 CFR 1910.1030 § g.2.i)
  2. Manage the handling and disposal of regulated medical wastes generated in isolation areas by using the same methods used for regulated medical wastes from other patient-care areas ( 270 ). Category II
  3. Use proper sharps disposal strategies ( 293 ). Category IC (OSHA: 29 CFR 1910.1030 � d.4.iii.A)

IV. Treatment and Disposal of Regulated Medical Wastes

  1. Treat regulated medical wastes by using a method (e.g., steam sterilization, incineration, interment, or an alternative treatment technology) approved by the appropriate authority having jurisdiction (AHJ) (e.g., state, Indian Health Service, or Veterans Administration) before disposal in a sanitary landfill. Category IC (States, AHJ)
  2. Follow precautions for treating microbiologic wastes (e.g., amplified cultures and stocks of microorganisms) ( 400 ). Category IC (DHHS: BMBL)

V. Special Precautions for Wastes Generated During Care of Patients with Rare Diseases

  1. When discarding items contaminated with blood and body fluids from VHF patients, contain these regulated medical wastes with minimal agitation during handling ( 36,109 ). Category II
  2. Manage properly contained wastes from areas providing care to VHF patients in accordance with recommendations for other isolation areas (Regulated Medical Waste: III B) ( 36,109,270 ). Category II
  3. Decontaminate bulk blood and body fluids from VHF patients by using approved inactivation methods (e.g., autoclaving or chemical treatment) before disposal ( 36,109 ). Category IC, II (States)
  4. When discarding regulated medical waste generated during the routine (i.e., nonsurgical) care of CJD patients, contain these wastes and decontaminate them by using approved inactivation methods (e.g., autoclaving or incineration) appropriate for the medical waste category (e.g., blood, sharps, or pathological waste) ( 36,270,273,336 ). Category IC, II (States)
  5. Incinerate medical wastes (e.g., central nervous system tissues or contaminated disposable materials) from brain autopsy or biopsy procedures of diagnosed or suspected CJD patients ( 340,342 ). Category IB

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