Legionella Appendix Section

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Appendix Section

APPENDIX A

Membership and staff of the Maryland Scientific Working Group to Study Legionella in Water Systems
Scientific Working Group to Study Legionella in water distribution networks
J. Glenn Morris, Jr., MD, MPH&TM, Chair
Professor and Chairman, Department of Epidemiology and Preventive Medicine
Professor of Medicine
Professor of Microbiology and Immunology
University of Maryland School of Medicine
Charles Davis, MD
Associate Professor of Medicine
University of Maryland School of Medicine
Trish M. Perl, MD, MSc
Associate Professor of Medicine
Johns Hopkins University School of Medicine
Director, Hospital Epidemiology Program
Johns Hopkins Hospital
Matthew A. Wallace, MS, CIC
Infection Control Department
Franklin Square Hospital
Steven Snow, P.E.
Engineering Operations and Planning Manager
Johns Hopkins Hospital
Joseph P. Libonati, PhD
Science Applications International Corporation
Melissa McDiarmid, MD, MPH
Professor of Medicine
Director, Occupational Health Project
University of Maryland School of Medicine
John Koerner, MPH, CIH
J.F. Koerner Consulting, Inc.
Carmela Groves, RN, MS
Chief, Division of Outbreak Investigation
Epidemiology and Disease Control Program
Maryland Department of Health and Mental Hygiene
Working Group Staff
Robert Venezia, PhD
Maryland Department of Health and Mental Hygiene
Helen E. Bowlus. Esquire
Office of the Attorney General
David Torpey, ScD
Assistant Professor of Epidemiology and Preventive Medicine
University of Maryland School of Medicine
Anthony Amaroso, MD
Division of Infectious Diseases, Department of Medicine
University of Maryland School of Medicine
Rashid Chotani, MD
Johns Hopkins Hospital
Dotti Stout
Department of Epidemiology and Preventive Medicine
University of Maryland School of Medicine

APPENDIX B

Schedule of Public Scientific Meetings, Legionella Scientific Working Group
MARYLAND LEGIONELLA WORKING GROUP Scientific Sessions
November 16, 1999, 2:00-5:00 PM, University of Maryland
Location: Health Science Conference Room # 171,
Health Science Facility, 685 W. Baltimore Street
Session 1, Epidemiology
Dr. David Blythe, DHMH
Current reporting on legionella in Maryland
Results of recent Maryland hospital survey
Dr. Barry Fields, CDC
National data on occurrence of legionella
Session 2a, Diagnostic Considerations
Dr. Barry Fields, CDC
Approaches to diagnosis
Recommendations regarding availability of specific tests for hospital and state laboratories
November 23, 1999, 2:00-5:00 PM, University of Maryland
Location: Medical School Teaching Facility (MSTF) Atrium
Session 2a, Diagnostic Considerations (continued)
Dr. Lena Trivedi, Laboratory Administration, DHMH, and Carmela Groves, DHMH
Summary of methods for legionella identification/diagnosis available in local hospitals and at DHMH, including methods for screening of water distribution networks
Dr. Janet Stout
University of Pittsburgh
Diagnostic methods – current approaches, appropriate clinical methodology for hospitals, appropriate methodologies for environmental screening
Session 2b: water distribution networks
Maryland Department of the Environment
Maryland guidelines/issues related to legionella in water distribution networks
Dr. Al Dufours
Director, Microbiological and Chemical Exposure Assessment Research Division, EPA
EPA approaches to legionella in water distribution networks
Dr. Eason Lin
University of Pittsburgh
Current research on legionella in water distribution networks/water distribution network disinfection

December 7, 1999, 2:00-5:00 PM, University of Maryland
Location: MSTF Atrium
Session 3: Approach to guidelines
Dr. Richard Besser, Chief, Legionella Activity, CDC
Current CDC guidelines
Dr. Victor Yu, Chief, Infectious Diseases Section
Department of Veterans Affairs Pittsburgh Healthcare Systems
Allegheny Count, PA, guidelines
David F. Geary, Chairman, ASHRAE GPC-12 Committee
ASHRAE Legionella Guidelines
Dr. Barry Farr, Professor of Medicine and Hospital Epidemiologist
University of Virginia Health Sciences Center
Society of Healthcare Epidemiologists of America (SHEA)

APPENDIX C

CDC Criteria for Identification of a Legionella Case as "Confirmed," "Probable," or "Nosocomial"
DEFINITIONS
Legionellosis (Revised 9/96)
Source: CDC.MMWR. Case Definitions for Infectious Conditions Under Public Health Surveillance. May 2, 1997/Vol. 46/ No. RR-10.
Clinical description
Legionellosis is associated with two clinically and epidemiologically distinct illnesses: Legionnaires’ disease, which is characterized by fever, myalgia, cough, pneumonia, and Pontiac fever, a milder illness without pneumonia.
Laboratory criteria for diagnosis

Isolation of Legionella from respiratory secretions, lung tissue, pleural fluid, or other normally sterile fluids, or
Demonstration of a fourfold or greater rise in the reciprocal immunofluorescence antibody (IFA) titer to ³ 128 against Legionella pneumophila serogroup 1 between paired acute- and convalescent-phase serum specimens, or
Detection of L. pneumophila serogroup 1 in respiratory secretions, lung tissue, or pleural fluid by direct fluorescent antibody testing, or
Demonstration of L. pneumophila serogroup 1 antigens in urine by radioimmunoassay or enzyme-linked immunosorbent assay

Case classification
Confirmed: a clinically compatible case that is laboratory confirmed

"Probable Case"
The previously used category of "probable case," which was based on a single IFA titer, lacks specificity for surveillance and is no longer used.
Legionellosis (Legionnaires’ Disease) Note: old definitions
Source: CDC. MMWR. Case Definitions for Public Health Surveillance. October 19, 1990/Vol. 39/ No. RR-13.
Clinical description
An illness with acute onset, commonly characterized by fever, cough, and pneumonia that is confirmed by chest radiograph. Encephalopathy and diarrhea may also be included.
Laboratory criteria for diagnosis

Isolation of Legionella from lung tissue, respiratory secretions, pleural fluid, blood or any other normally sterile sites, or
Demonstration of a fourfold or greater rise in the reciprocal immunofluorescence (IF) antibody titer to ³ 128 against Legionella pneumophila serogroup 1, or
Demonstration of L. pneumophila serogroup 1 in lung tissue, respiratory secretions, or pleural fluid by direct fluorescence antibody testing, or

Demonstration of L. pneumophila serogroup 1 antigens in urine by radioimmunoassay

Case classification
Probable: a clinically compatible illness with demonstration of a reciprocal antibody titer ³ 256 from a single convalescent-phase serum specimen
Confirmed: a case that is laboratory confirmed

Definition of Nosocomial Legionnaires Disease
Source: CDC. MMWR. Guidelines for Prevention of Nosocomial Pneumonia. January 3, 1997/Vol. 46/ No. RR-1.
The incubation period for Legionnaires’ disease is usually 2-10 days; thus, for the purposes of this document and the accompanying HICPAC recommendations laboratory-confirmed legionellosis that occurs in a patient who has been hospitalized continuously for ³ 10 days before the onset of illness is considered a definite case of nosocomial Legionnaires’ disease, and laboratory-confirmed infection that occurs 2-9 days after hospital admission is a possible case of the disease.

APPENDIX D

Protocol of Allegheny County Health Department for Primary Prevention of Legionella Infection

APPENDIX E

Hospital Infection Control Practices Advisory Committee (HICPAC) guidelines for prevention of nosocomial Legionnaire’s disease

Hospital Infection Control Practices Advisory Committee
(Last update: Tuesday, March 26, 1996)
Source: www.cdc.gov/ncidod/diseases/hip/pneumonia/2_legion.htm

Recommendations for Prevention of Nosocomial Legionnaires' Disease

I. STAFF EDUCATION AND INFECTION SURVEILLANCE
A. Staff Education
Educate (1) physicians to heighten their suspicion for cases of nosocomial Legionnaires' disease
and to use appropriate methods for its diagnosis, and (2) patient-care, infection-control, and
engineering personnel about measures to control nosocomial legionellosis.(659-661)
CATEGORY IA
B. Surveillance
1. Establish mechanism(s) to provide clinicians with appropriate laboratory tests for the diagnosis of Legionnaires' disease.(386,414,415,419,704) CATEGORY IA
2. Maintain a high index of suspicion for the diagnosis of nosocomial Legionnaires' disease,
especially in patients who are at high-risk of acquiring the disease (patients who are
immunosuppressed, including organ-transplant patients, patients with AIDS, and patients
receiving systemic steroids; are >65 years of age; or have chronic underlying disease such as
diabetes mellitus, congestive heart failure, and chronic obstructive lung disease). (385,386,400,402-406,412) Refer to the accompanying background document for
definition of nosocomial legionellosis. CATEGORY II
3. No Recommendation for routinely culturing water distribution networks for Legionella
spp.(271,385,429,433,435,436,438-440,456,705) UNRESOLVED ISSUE
II. INTERRUPTION OF TRANSMISSION OF LEGIONELLA SPP.
A. Primary Prevention (Preventing Nosocomial Legionnaires' Disease When No Cases
Have Been Documented)
1. Nebulization and other devices
a. (1) Use sterile (not distilled, nonsterile) water for rinsing nebulization devices and other
semicritical respiratory-care equipment after they have been cleaned and/or disinfected. (258,271,706) CATEGORY IB
(2) No Recommendation for using tap water as an alternative to sterile water to rinse reusable
semicritical equipment and devices used on the respiratory tract, after they have been subjected
to high-level disinfection, whether or not rinsing is followed by drying with or without the use of
alcohol. UNRESOLVED ISSUE
b. Use only sterile (not distilled, nonsterile) water to fill reservoirs of devices used for
nebulization.(241,252,258,271,706) CATEGORY IA
c. Do not use large-volume room-air humidifiers that create aerosols (eg, by venturi principle,
ultrasound, or spinning disk) and thus are really nebulizers, unless they can be sterilized or
subjected to high-level disinfection daily and filled only with sterile water.(252,706) CATEGORY IA
2. Cooling towers
a. When a new hospital building is constructed, place cooling tower(s) in such a way that the
tower drift is directed away from the hospital's air-intake system, and design the cooling towers
such that the volume of aerosol drift is minimized.(422,707) CATEGORY IB
b. For operational cooling towers, install drift eliminators, regularly use an effective biocide,
maintain the tower according to manufacturers' recommendations, and keep adequate
maintenance records. (422,464,708) CATEGORY IB
3. Water-Distribution System
a. No Recommendation for routinely maintaining potable water at the outlet at => 50°C or
<20°c, or chlorinating heated water to achieve 1-2 mg/L free residual chlorine at the
tap.(385,429,440,447-450) UNRESOLVED ISSUE
b. No Recommendation for treatment of water with ozone, ultraviolet light, or heavy-metal
ions.(391,460-463,466) UNRESOLVED ISSUE
B. Secondary Prevention (Response to Identification of Laboratory-Confirmed Nosocomial Legionellosis)
When a single case of laboratory-confirmed, definite nosocomial Legionnaires' disease is
identified, OR if two or more cases of laboratory-confirmed, possible nosocomial Legionnaires'
disease occur within 6 months of each other (refer to background document for definition of
definite and possible nosocomial Legionnaires' disease.):
1. Contact the local or state health department or the CDC if the disease is reportable in the state
or if assistance is needed. CATEGORY IB
2. If a case is identified in a severely immunocompromised patient such as an organ-transplant
recipient, OR if the hospital houses severely immunocompromised patients, conduct a combined
epidemiologic and environmental investigation (as outlined from II-B-3-b-1 through II-B-5,
below) to determine the source(s) of Legionella spp. CATEGORY IB
3. If the hospital does not house severely immunocompromised patients, conduct an
epidemiologic investigation via a retrospective review of microbiologic, serologic, and
postmortem data to identify previous cases, and begin an intensive prospective surveillance for
additional cases of nosocomial Legionnaires' disease. CATEGORY IB
a. If there is no evidence of continued nosocomial transmission, continue the intensive
prospective surveillance (as in II-B-3, above) for at least 2 months after surveillance was begun.
CATEGORY II
b. If there is evidence of continued transmission:
(1) Conduct an environmental investigation to determine the source(s) of Legionella spp. by
collecting water samples from potential sources of aerosolized water, following the methods
described in Appendix C [see CDC web page for this appendix] and saving and subtyping isolates of Legionella spp. obtained from patients and environment.(241,258,422-428,452,454) CATEGORY IB
(2) If a source is not identified, continue surveillance for new cases for at least 2 months, and,
depending on the scope of the outbreak, decide on either deferring decontamination pending
identification of the source(s) of Legionella spp., or proceeding with decontamination of the
hospital's water distribution system, with special attention to the specific hospital areas involved in the outbreak. CATEGORY II
(3) If a source of infection is identified by epidemiologic and environmental investigation, promptly decontaminate it.(466) CATEGORY IB
(a) If the heated-water system is implicated:
i. Decontaminate the heated-water distribution network either by superheating (flushing for at least 5 minutes
each distal outlet of the system with water at 65ºC), OR by hyperchlorination (flushing for at least 5 minutes all outlets of the system with water containing > or = 10 mg/L free residual chlorine).(450,452,456,457) Post warning signs at each outlet being flushed to prevent scald injury to patients, staff, or visitors. CATEGORY IB
ii. Depending on local and state regulations regarding potable water temperature in public
buildings,(458) maintain potable water at the outlet at 50ºC or <20ºC, or chlorinate heated water
to achieve 1-2 mg/L free residual chlorine at the tap in hospitals housing patients who are at high
risk of acquiring nosocomial legionellosis (eg, immunocompromised patients).(385,429,440,447-450) (See Appendix B.) CATEGORY II
iii. No Recommendation for treatment of water with ozone, ultraviolet light, or heavy-metal
ions.(391,460,461,463) UNRESOLVED ISSUE
iv. Clean hot-water storage tanks and water heaters to remove accumulated scale and
sediment.(393) CATEGORY IB
v. Restrict immunocompromised patients from taking showers, and use only sterile water for their oral consumption until Legionella spp. becomes undetectable by culture in the hospital water.(430) CATEGORY II
(b) If cooling towers or evaporative condensers are implicated, decontaminate the
cooling-tower system using the protocol outlined in Appendix D.(464) CATEGORY IB
(4) Assess the efficacy of implemented measures in reducing or eliminating Legionella spp. by
collecting specimens for culture at 2-week intervals for 3 months. CATEGORY II
(a) If Legionella spp. are not detected in cultures during 3 months of monitoring, collect cultures
monthly for another 3 months. CATEGORY II
(b) If Legionella spp. are detected in one or more cultures, reassess the implemented control
measures, modify them accordingly, and repeat decontamination procedures. Options for repeat
decontamination include the intensive use of the same technique utilized for initial decontamination, or a combination of superheating and hyperchlorination. CATEGORY II
(5) Keep adequate records of all infection control measures, including maintenance procedures,
and of environmental test results for cooling towers and potable-water distribution networks. CATEGORY II

APPENDIX F

Scenarios: Legionella monitoring in hospital water distribution networks
We have developed several scenarios to help define recommended practices in different healthcare settings. We assume the following for all of the listed scenarios.
We define high risk patients as:
solid organ transplant
bone marrow transplant
person on high doses of steroids (>20 mg/day) or other immunosuppressive agent
We anticipate that each facility will have a "Legionella Team," as outlined in the Recommendations of this report. As part of this team effort, the infection control practitioner will meet with facility personnel to review maintenance practices. Facility personnel should maintain a log that includes dates and type of water distribution network maintenance, including hot water tank cleaning, dates of temperature adjustments, etc. Equipment should be maintained per manufacturer’s recommended practices. Facilities personnel should inform infection control practitioners of the location of the cooling towers, and conduct (and log) routine and regular maintenance of cooling towers and water distribution networks. Cooling towers should be directed away from the air intakes of the facility and equipped with drift eliminators. All positive clinical and environmental cultures for legionella should be reported to the hospital Infection Control office. Construction, renovation or installation of new equipment should follow local plumbing code for potable water distribution networks and should be in keeping with the facilities construction policy.

Scenario 1 applies to hospitals of > 400 beds.
Scenario 1: A large tertiary care teaching hospital with 700 beds, of which 100 are licensed intensive care beds, has active renal, liver, heart and lung transplant programs and an active oncology service that offers bone marrow transplants. The hospital has hot water tanks that supply heated potable water; the hospital physical plant is older, and there is substantive scaling and sediment in the system. No nosocomial legionella infections have occurred in the past two years.
Approaches:

Educate healthcare workers and maintain a heightened suspicion for legionella as a cause of nosocomial pneumonia
Have urine antigen testing and the ability to do legionella cultures available in hospital laboratory
Culture/test all high risk patients with community and hospital acquired pneumonia for legionella.
Use sterile water in respiratory equipment including devices that nebulize.
Limit or eliminate humidifiers.
Create a Legionella Team that answers to the hospital Infection Control Committee.

Environmental culturing would be appropriate:
Quarterly from at least 14 distal sites (showerheads and faucets): some distal sites located in intensive care, bone marrow transplant and solid organ transplant or other high risk units.
Quarterly from all hot water tanks and sources (instantaneous hot water distribution networks).

In the initial testing, 48% of distal sites are culture positive for legionella, including sites in the bone marrow transplant unit. No cases of nosocomial legionella infection are identified, despite heightened surveillance efforts. However, because of the presence of many high risk patients, the hospital initiates a program of superheating, combined with cleaning and descaling of the hot water distribution network. While there is an initial reduction in percent positive sites to 20%, the percentage positive returns to 45% when the system is re-tested four weeks later. Under these circumstances, the hospital installs a copper-silver ionisation system in the hot water supply. Within two months, all cultures are negative for legionella.
After one year of negative cultures, the hospital decreases the frequency of culturing to once every six months, and only cultures from distal sites on the solid organ transplant and bone marrow transplant unit. The hospital continues to culture/test all high risk patients with community and hospital acquired pneumonia for legionella.

Scenario 2 applies to hospitals of <400 beds and assumes that bone marrow and solid organ transplants are not performed. If bone marrow or solid organ transplants are performed, follow scenario 1.
Scenario 2: A mid-sized community hospital with 180 beds, of which 15 are licensed intensive care beds, has an active oncology service, and has hot water tanks that supply heated potable water. The current hospital facility was built within the past five years. No nosocomial legionella infections have occurred in the past two years.
Recommendations:

Educate healthcare workers and maintain heightened suspicion for legionella as a cause of nosocomial pneumonia
Implement urine antigen testing in hospital laboratory and assure ready access for specimens to a laboratory that can perform cultures
Culture/test high-risk patients with community and hospital acquired pneumonia for legionella.
Use sterile water in respiratory equipment including devices that nebulize.
Limit or eliminate humidifiers.
Establish a "Legionella Team" that answers to the hospital Infection Control Committee.

Environmental culturing would be appropriate:
Semi annually from at least 10 distal sites (showerheads and faucets): some distal sites located in intensive care and high-risk units.
Annually include all hot water tanks and sources (instantaneous hot water distribution networks)

The hospital finds that, while some sites are culture-positive for legionella, the percent of sites positive never exceeds 10%. Under these circumstances, remediation efforts are not attempted. However, the hospital continues to maintain careful surveillance for nosocomial legionella, particularly among its oncology patients; continues regular environmental surveillance; and carefully maintains the hot water distribution network.

Scenario 3: A small community hospital with 60 beds, of which 5 are licensed intensive care beds, does not have an inpatient oncology service, and has hot water tanks that supply heated potable water. The current hospital facility was build 15 years ago. No nosocomial legionella infections have been diagnosed in the past two years.
Recommendations:

Educate healthcare workers and maintain heightened suspicion for legionella as a cause of nosocomial pneumonia
Implement urine antigen testing in hospital laboratory and assure access to a laboratory that can perform cultures
Culture/test high-risk patients with community and hospital acquired pneumonia for legionella.
Use sterile water in respiratory equipment including devices that nebulize.
Limit or eliminate humidifiers.
Place responsibility for Legionella control with the hospital Infection Control Committee, making certain that a representative from facilities management is on the committee.

The hospital elects to follow the Allegheny County, PA, guidelines, and undertakes annual environmental testing from 10 distal sites and all hot water tanks.

The hospital finds that 20% of cultures are positive for legionella. Remediation efforts are not attempted. However, the hospital continues to maintain careful surveillance for nosocomial legionella, including urinary antigen testing in suspected cases of nosocomial pneumonia; continues regular environmental surveillance; and carefully maintains the hot water system.

Scenario 4 applies to all nursing homes, rehabilitation and intermediate care facilities regardless of number of beds.
Scenario 4: A 100 bed licensed nursing home admits patients with diabetes, cancer, and lung and heart disease for care. The hot water tanks supply heated potable water. No known nosocomial legionella infections have occurred in the past two years.
Recommendations:

Educate healthcare workers and maintain heightened suspicion for legionella as a cause of nosocomial pneumonia
Identify a laboratory which can perform urinary antigen and culture for legionella in a timely fashion, and make certain that physicians who have patients within the facility are aware of the availability of such testing
Encourage physicians to culture/test high risk patients with community and hospital acquired pneumonia for legionella.
Notify the institution’s infection control practitioner of a suspected case of nosocomial pneumonia among patients.
Use sterile water in respiratory equipment including devices that nebulize.
Limit humidifiers
Place responsibility for legionella control with the institution’s infection control practitioner, working together with a designated representative from facilities management.

Environmental culturing would be appropriate when:

a case of nosocomial legionella pneumonia is identified or
a previously documented cluster of nosocomial legionella cases has occurred (past 2 years), or
an ongoing endemic problem of legionella disease among patients is identified.

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