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© Special Pathogens Laboratory
Janet E. Stout, PhDDirector, Special Pathogens LaboratoryResearch Associate ProfessorUniversity of Pittsburgh
LEGIONNAIRES’ DISEASEFrom Philly to Flint and Beyond
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40th Anniversary: 1976 to 2016
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1976 Happenings in Philadelphia
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The Bellevue-Stratford Hotel
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1976 Philadelphia (Philly)
• 58th convention of the American Legion held July 21-24
• Mysterious illness effects 221 and kills 34
• Causative agent of pneumonia would not be identified until 1977
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Legionella pneumophila• CDC microbiologist
Joseph McDade sees bacteria for the first time over Christmas 1976
• Bacteria does not grow on standard culture media –new media developed (BCYE) in 1977
• First diagnostic test developed – Direct Fluorescent Antibody (DFA) test
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1980: Research Begins in Pittsburgh
• More than 30 years studying Legionnaires’ disease I’m a
Legionellologist
• Mission: What I’ve learned can help you
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How?Microbiologist with a Minor in Plumbing!
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MY HISTORY WITH LEGIONELLA IN BUILDING WATER SYSTEMS
First – A History Lesson
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Research Pioneers in 1982
• Over 100 nosocomial cases identified in 5 years in one hospital
• An epidemic redefined - endemic disease and the source was the hospital water system – not a cooling tower!Janet E. Stout and Victor L. Yu
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• Not a common source for sporadic and hospital-acquired cases
• More commonly associated with large community outbreaks
Paradigm Shift: Not Cooling Towers
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Paradigm Shift
Potable water especially in hospitals (and other buildings)
with complex hot water systems, is the most important
source of Legionella transmission.
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Today’s Topics
• The continued challenge of Legionnaires' disease
• Understanding Legionella in the built environment
• Role of Legionella testing in disease prevention
• Approaches to prevention
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THE CHALLENGE OF LEGIONNAIRES’ DISEASE
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The Disease
• Is Legionella reallyan opportunistic pathogen?
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What Is Legionellosis?
• Legionnaires’ disease is pneumonia, caused by bacteria in the family Legionellaceae.
• Most often caused by Legionella pneumophila, serogroup 1
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Are You At Risk?
• Elderly (>50)• Smokers• Immunocompromised Transplant patients High-dose steroids for lung disease Diabetes Cancer
• Approx. 25% cases no known risk factors
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Legionnaires’ Disease
• Most cases in people with health conditions that increase risk
Early treatment with effective antibiotics reduces mortality
Mortality as high as 30% for healthcare acquired cases
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TRANSMISSION AND HEALTHCARE-ACQUIRED CASES
Epidemiology and Infection Prevention
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Legionellain water (reservoir)
+Transmission to the host(exposure)
+Susceptible Host
Risk of Acquiring Disease
Exposure Alone Doesn’t = Disease Acquisition
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Modes of Transmission for Legionnaires’ disease
• Aerosolization
• Aspiration
• Direct instillation into the patient (tap water rinsing of nasogastric tubes, respiratory tubing, etc)
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IS LEGIONNAIRES’DISEASECONTAGIOUS?
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Cooling Tower 300km Away
• Outbreak cluster Portugal• Patient 1 was a 48 yr old male
worked at cooling tower complex where outbreak occurred
• Travels home 300km where 74 yomother provides care and also becomes ill
• Same sequence type
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No Person-to-Person Transmission
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Cases and Outbreaks
• Majority of cases are sporadic and not outbreak-associated = no investigation
• Outbreak is defined as two or more cases related in time & location = investigation
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PREVENTING LEGIONNAIRES’ DISEASE
How are we doing?
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Legionella Is Winning
• Legionnaires’disease is increasing
• Legionella proves to be a difficult opponent!
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Increasing U.S. Cases 1998–2014
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Consider This…
• Legionellosis cases have increased substantially more than
200% in last 10 years
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Why Increase in Reported Cases?
• Increase in diagnostic testing = more cases identified
• Environmental factors?
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Wet Weather & Legionnaires’ Disease?
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Morbidity Mortality Weekly Report (MMWR). August 14, 2015/64 (31); 842-848. Surveillance for Waterborne Disease Outbreaks Associated with Drinking Water — United States, 2011–2012
Many Cases Linked to Drinking Water
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Legionella in Water
Centers for Disease Control and Prevention (CDC) reported:
• Legionella accounted for 66% of reported drinking water–associated outbreaks
• Legionella in building plumbing systemslead to drinking water-associated outbreaks.
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How does Legionellaget into our water?
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Legionella in Source Water (1987)
• “Public water supplies may contaminate the plumbing systems of hospitals and other large buildings.”
From: States, SJ, Conley LF, Kuchta JM, et al. Survival and multiplication of L. pneumophila in municipal drinking water systems. Appl. Environ. Microbiol. 1987; 53: 979-986.
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Ground, Surface, and Potable Waters and Legionella (1997)
• “Results of this study confirm the ubiquity of Legionella in aquatic environments, even ground water.”
Lye, D, Fout S, Crout S. et al. Survey of ground, surface, and potable waters for the presence of Legionella species by PCR, culture, and immunofluorescent staining. Water Res. 1997; 31: 287-293.
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Origins of Legionella in Building Water Systems?
12
3
4
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Origins of Legionella
• Incoming potable water (undetectable or very low conc.)
• Systems with warm water, such as water distributions systems and air cooling systems (provide growth factors)
• Biofilms within these systems provide growth-promoting conditions
© Special Pathogens Laboratory
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Pressure Change Increased Legionella
• Isolation of Legionella pneumophila from the hospital water supply
• Upsurge in cases following a pressure drop caused by a pump failure
• Documentation of a 30-fold increase in concentration of Legionella in the water when this “pressure shock” was artificially recreated.
© Special Pathogens Laboratory
Pressure Change Increased Legionella
150 CFU/mL 1140 CFU/mL 5370 CFU/mL
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Community Water System Outbreak: Senior Apartment Complex
• Legionnaires’ disease case-finding algorithm, attack rates, and risk factors during a residential outbreak among older adults: an environmental and cohort study
Benjamin J Silk, Jennifer L Foltz, Kompan Ngamsnga, Ellen Brown et al. BMC Infectious Diseases 2013, 13:291
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Probable Causes
1. Elderly population with comorbidity 2. Water heaters had low temperatures
at the bottom of tanks (range: 70–100°F/21.1–37.8°C)
3. Low or no chlorine4. Interruptions in water service
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Interruption In Water Service = Brown Water Event
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Interruption in Water Service
1. Three-quarters (75%) of residents who were interviewed noted at least one interruption in water service since August 1st.
2. More than half of residents (56%) reported changes in the taste, odor, or color of their water during the same period.
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Why Do Outbreaks Continue?
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Legionella-Related Anxiety
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Five Stages Of Coping with Legionella
1. Denial2. Bargaining3. Depression4. Acceptance5. Medication
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1. Denial
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Denial
Most wait to address
the problem until after
a case of Legionnaires’
disease is diagnosed.
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Approaches to Disease Prevention
• REACTIVE After 1 transplant
patient or 2+ cases within 6 months• Combined
epidemiologic and environmental investigation
• Legionellasource identified = decontaminate
• PROACTIVE Perform
environmental surveillance before cases Perform clinical
surveillance to identify unrecognized cases
• Legionella source identified = decontaminate
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Proactive Approach Reduced Legionnaires’ Disease
Am. J. Infection Control 2005; 33(6):360-367
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Our Study Results of 48 Hospitals
• Proportion of hospitals performing environmental surveillance = 65%
• Proportion of cases hospital-acquired: Pre-guideline = 33% Post-guideline = 9%
• Proportion that started water treatment (disinfection) = 44%
© Special Pathogens Laboratory
2 . Bargaining
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Bargaining
• Legionella is everywhere
• There’s hardly any cases
• It is too costly to control/monitor
• If I don’t know, I’m not responsible
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Myth: Legionella Is Everywhere
• Published studies find: 20–70% of
buildings and 30-50% of
cooling towers colonizedwith Legionella
• Legionella is not ubiquitous (everywhere)!
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Many Cases of This Disease
• In the U.S. approximately 600,000 adults are diagnosed with community-acquired pneumonia requiring hospitalization
• A minimum of 2-5% are caused by Legionella, as many as 30,000 cases/year
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Under ReportingDue to Missed Diagnosis
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Results for 37 Cases
41% of Legionella cases were missed when following current
Infectious Disease Society recommendations for
Legionella testing
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Many Cases Still Missed
• Diagnostic tests for Legionella not routine – often not done
• Many studies have demonstrated under reporting/missed diagnosis
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PREVENTING LEGIONNAIRES’ DISEASE OUTBREAKS
How are we doing?
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Legionellosis in the U.S.
Outbreaks continue to occur (building warm water systems, cooling towers, fountains)
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Outbreaks 2000 to 2014
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Hospitals at Significant Risk According to Recent
CDC Report
Legionella in hospitals –accounted for 57% of all cases and 85% of deaths
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Outbreaks in Nursing Homes & Assisted Living Facilities
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HOSPITAL OUTBREAK LINKED TO NEW CONSTRUCTION
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Hospital Construction
• New $135M 12-story cardiac care patient tower
• 11 cases & one death shortly after opening
• 74% of distal outlets positive for Legionella within one month of opening
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Legionnaires' Cases in Quebec City
TOTAL=180
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Outbreak
• Canada’s biggest and deadliest in 25 years
• 89 cooling towers disinfected
• Source=Cooling Tower
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2013 Outbreak in Germany
• Warstein, Germany 165 cases, 12 ICU, 2 deaths caused by
Legionella pneumophila, serogroup 1
Outbreak strain found in 2 cooling towers + other sources – including wastewater from a brewery!
Public health communication
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Public Safety Announcement
“Whether or not the Warsteiner brewery is found to be the breeding ground for the Legionella bacteria, officials have been making it clear that …
the beer is completely safe to drink.”
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DRINKING WATERWhat Ben Franklin said
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with water comes bacteria Legionella.”
“With wine comes wisdom,
with beer comes freedom,
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Water Quality & LD in Flint, Mich.
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Outbreak Flint, Michigan91 cases and 12 Deaths
• April 2014 switch source water from Lake Huron to Flint River
• 45 cases from June 2014 to 2015
• 46 cases from May to October 2015
• October 2015 switch source back to Lake Huron
© Special Pathogens Laboratory
Flint Legionnaires’ Disease Outbreak
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2015: Summer of Legionella
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South Bronx Outbreak
• 130 cases, 12 deaths
• Declared over August 20, 2015
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© Special Pathogens Laboratory
Outbreak Linked to Hotel Cooling Tower
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NEW YORK STATE EMERGENCY REGULATIONS
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Emergency Regulation
• Cooling towers must be registered
• Legionella testing every 90 days
• Inspection• Certification• Maintenance
program
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PREVENTING LEGIONNAIRES’ DISEASE
Is It Worth the Effort (Money)?
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U.S. Healthcare Costs Associated with Legionnaires’ Disease
Total hospitalizationcosts
$101 - $321 millionper year
Collier s.A., L. J. Stockman, l.A. Hicks, l. E. Garrison, f. J. Zhou and m. J. Beach. Epidemiol. Infect. (2012), 140, 2003–2013.
© Special Pathogens Laboratory
Legionella Outbreaks Are Costly
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Costly Outbreaks
• Even a single case can dramatically affect an organization
$700,000
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$ 10 Million
Outbreak Response:Pittsburgh VA Hospital
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Outbreak Response:Illinois Vets Home
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3. Depression
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The Times They Are a-Changin’
New Paradigm
for Prevention
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ASHRAE Proposes a Standard to Prevent Legionnaires’ Disease
American Society of Heating, Refrigerating and Air-conditioning Engineers
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4. Acceptance
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• First Legionellastandard in the United States.
• ApprovedJune 26, 2015
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Purpose of ASHRAE Standard 188
Establish minimum Legionellosis risk management requirements for building water systems.
© Special Pathogens Laboratory
The Real Purpose of ASHRAE Standard 188
To help engineers and infection preventionistscommunicate more effectively
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ASHRAE 188
Water Safety and Management Plans
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New Responsibilities
BUILDING OWNERS & FACILITY MANAGERS
• Responsible for implementing ASHRAE 188 requirements and safeguards to protect against Legionella
• Assist building owners with Program development and review, monitoring water systems and results interpretation
WATERMANAGEMENT TEAM
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New Responsibilities &
Liabilities
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Building Operating Management (Facilitiesnet.com) ASHRAE 188
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Compliance
The building shall be surveyed to determine whether it has one or more of the listed
water systems and/or the factors described that relate to
risk for Legionellosis.
© Special Pathogens Laboratory
Does ASHRAE 188 Apply to Me?
• Section 5: Building Survey Building owners must survey all existing
buildings for the following:oNon-potable Systems
oBuilding Characteristics
© Special Pathogens Laboratory
Water Systems Covered by 188
• Potable and non-potable water systems, in the building or on the site Includes building water distribution systems
(including centralized potable water heater systems) Cooling towers, evaporative condensers Whirlpools or spas Ornamental fountains, misters, atomizers, air
washes, humidifiers or other non-potable water systems or devices that release water aerosols in the building or on the site
© Special Pathogens Laboratory
Section 5.2: Building Characteristics
• Multiple housing units• > 10 stories high (including below grade)• Patient stays exceed 24 hours• One or more areas for purpose of housing
or treating occupants receiving treatment for burns, chemotherapy, organ transplantation or bone marrow transplantation
© Special Pathogens Laboratory
Section 5.2: Building Characteristics
• One or more areas for the purpose of housing or treating occupants that are immuno-compromised, at-risk, taking drugs that weaken immune system, have renal disease, have diabetes, or chronic lung disease
• Housing occupants over the age of 65.
© Special Pathogens Laboratory
Elements of Water Management Program
Program Team – Persons responsible for Program development and implementation.
Water Systems/Flow Diagrams – Describe potable and non-potable water systems and develop water system-schematics.
Water System Analysis/Control Measures – Evaluate where hazardous conditions may occur and decide where control measures should be applied.
Monitoring/Corrective Actions – Establish procedure for monitoring whether control measures are within operating limits and, if not, take corrective actions.
Confirmation – Establish procedure to confirm Program is being implemented as designed (verification) and the Program effectively controls the hazardous conditions (validation).
Documentation – Establish documentation and communication procedures for all activities of the Program.
© Special Pathogens Laboratory
ASHRAE 188 ComplianceGood News, Bad News
• Standard is not prescriptive – Good News - You get to make lots of
decisions
Bad News - You get to make lots of decisions
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ASHRAE 188: Mind the Gaps
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Testing for Legionella
• Legionella testing isn’t required to validate that the risk management program is working.
• The ProgramTeam decides whether to test for Legionella.
• BUT testing is the only way to validate efficacy of your control measures and assess threat from Legionella.
© Special Pathogens Laboratory
Control Measures
• Control measures are also at the discretion of the Program Team
• Example – hot water temperatures The standard refers back to the ASHRAE
guideline which recommends temperatures• Hot water generation 60oC (140oF) and 51oC
(124oF) upon return in healthcare facilities • All other facilities are to generate hot water at 49oC
(120oF) or above.
© Special Pathogens Laboratory
Elements of Water Management Program
Program Team – Persons responsible for Program development and implementation.
Water Systems/Flow Diagrams – Describe potable and non-potable water systems and develop water system-schematics.
Water System Analysis/Control Measures – Evaluate where hazardous conditions may occur and decide where control measures should be applied.
Monitoring/Corrective Actions – Establish procedure for monitoring whether control measures are within operating limits and, if not, take corrective actions.
Confirmation – Establish procedure to confirm Program is being implemented as designed (verification) and the Program effectively controls the hazardous conditions (validation).
Documentation – Establish documentation and communication procedures for all activities of the Program.
© Special Pathogens Laboratory
Knowledge
The program team shall have knowledge of
the building water system design and water management as it relates to Legionellosis
© Special Pathogens Laboratory
© Special Pathogens Laboratory
Test Your Knowledge: True or False?
• Legionella is ubiquitous (everywhere).• If chlorine levels at or above 0.5 mg/L in the
supply water, Legionella is controlled.• Only old buildings have Legionella problems.• If total bacteria are controlled, Legionella is
controlled.• Water and energy conservation approaches
minimize Legionella risk.
© Special Pathogens Laboratory
Water-Saving Low Flow Faucets
Manual Faucet Sensor Faucet
© Special Pathogens Laboratory
Disturbing Findings
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WHY TEST?
Environmental Monitoring for Legionella: Key to Prevention
© Special Pathogens Laboratory
Testing Can Be Revealing
• Hospitals performing Legionellaenvironmental testing are more likely to prevent cases of hospital-acquired Legionnaires’ disease
Squier CL, Stout JE, Krystofiak S, McMahon J, Wagener MM, Dixon B. Yu VL. Am. J. Infect. Control 2005; 33(6): 360-367.
Approach to Environmental Sampling
• Select a minimum of 10 distal sites (faucets or showers) that roughly represent the water distribution system, plus hot water tanks or recirc. line.
• Include sites on multiple floors and wings, high risk areas like oncology, transplant units, medical surgical units.
Calculating Percent Positivity
• Number of outlets positive for Legionella of 10 distal sites (faucets or showers) that were tested
• Estimating the probability of a patient “bumping into” Legionella (percent positive)
• If >30% risk increases, especially if L. pneumophila, serogroup 1 is present
© Special Pathogens Laboratory
Risk – Building Potable Water
Risk of Legionnaires’ disease was better predicted by the
proportionof water system sites
testing positive for Legionellathan by the
concentration of Legionella bacteria.
Kool J L, et al. Infect. Control Hosp. Epid. 1999 20:797-805
© Special Pathogens Laboratory
0%
20%
40%
60%
80%
100%
120%
Dis
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High (>30%) Legionella Distal Site Positivity And Cases Prior to Treatment
Distal Site Positivity
No Cases after Treatment (NH2Cl)Cases
© Special Pathogens Laboratory
Monitoring of Cooling Towers
© Special Pathogens Laboratory
Can You Tell by Looking?
>3000 CFU/mL Legionella pneumophila serogroup 1
Automated dosing ofchemical biocides and clean clear water
© Special Pathogens Laboratory
Microbiological Testing: HPC (Total) Bacteria
What Can We Learn about Legionella from an HPC Test?
© Special Pathogens Laboratory
© Special Pathogens Laboratory
Heterotrophic Plate Count (HPC) Bacteria Testing
• HPC method does not detect Legionella
• HPC cannot be used to predict presence or absence of Legionella
• HPC counts can be low when Legionellais high
© Special Pathogens Laboratory
Heterotrophic Plate Count (HPC) Bacteria Testing
Effective Use of HPC or ATP Test:• Use as a biocide performance
indicator for general microbiological fouling
• An inexpensive early warning of a process or biocide application upset
• Not a substitute for Legionella culture
© Special Pathogens Laboratory
2015 Publication
© Special Pathogens Laboratory
Is the Sky Falling?
If I Find Some Legionella?
© Special Pathogens Laboratory
What is an acceptable amount
of Legionella?
© Special Pathogens Laboratory
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IS ZERONECESSARY?
© Special Pathogens Laboratory
Zero Legionella is virtually impossible to achieve in complex
water systems
Don’t Chase Zero
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Not All Legionella Are Dangerous
© Special Pathogens Laboratory
• Zero Legionella is nearly impossible in complex water systems
• Many species of Legionella can be present at any given time
• Of 58 species only half pose risk; Legionella pneumophila serogroup 1 causes majority of cases of Legionellosis
Don’t Chase Zero
© Special Pathogens Laboratory
Risk Criteria Based on Environmental Monitoring Results
• Concentration-based thresholds that establish target values in CFU per liter or milliliter
OK for cooling towers as a performance-based target (not health-based)
• Colonization rate or proportion of distal sites in the water system that are positive for Legionella
Best for hospitals and building water systems
© Special Pathogens Laboratory
Meaning for You
• Sampling the water system of a building can give you a meaningful “snapshot” of the colonization status.
© Special Pathogens Laboratory
• Methods for Legionella detection and quantitation Standard culture – validated/gold
standard Non-culture based molecular methods
• Quantitative Polymerase Chain Reaction (qPCR)
• Next Generation Sequencing (NGS)
Detection of Legionella
“Apples To Apples”or
“Apples To Oranges”?
Laboratory Testing
Did you know that labs differ in
their methods for Legionella
testing & identification?
© Special Pathogens Laboratory
Standard Culture Method
• Processing Methods Pretreatment (heat and/or acid) Filtration (yes/no or how much) Culture media (types and how many)
• Identification (ID) Methods Only presumptive agglutination test? Definitive ID with DFA or sequencing for
unusual species?
© Special Pathogens Laboratory
Culture for Legionella
Sometimes it’s like finding Waldo
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This Is Waldo
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Found Waldo (Legionella)
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Acid Pretreatment
H
S
Heat Pretreatment
Selective Antibiotic-containing
Culture Media
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Use of Molecular Methods for Detection of Legionella
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What is Quantitative Polymerase Chain Reaction (qPCR)?
© Special Pathogens Laboratory
• Relies on highly specific amplification of the target gene sequence
• Fluorescent reporter molecules that allow quantification of PCR products
• qPCR allows many samples to be processed in a short amount of time
qPCR Methodology
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• Allows for the simultaneous detection and identification of L. pneumophila and L. pneumophila serogroup 1 Detects gene for LPS
Advance: qPCR for LP1
Merault, et al. APPLIED AND ENVIRONMENTAL MICROBIOLOGY, Mar. 2011, p. 1708–1717
Molecular Testing: Quantitative PCR (qPCR)
• Limitations Cannot
discriminate between live and dead cells Genomic units
(GU) do not directly correlate to CFU
• Benefits Rapid Genus and species
specific probes Good agreement
with culture with Legionella pneumophila and L. pneumophila, serogroup 1 probes
© Special Pathogens Laboratory
DISINFECTION APPROACHES
I Have Legionella…Now What?
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DISINFECTION OPTIONS
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Secondary Disinfection Methods
• Thermal shock treatment(heat & flush)
• Shock chlorination (>10 mg/L residual), may require water tanks to be 20-50 mg/L
• Continuous supplemental chlorination (2-4 mg/L)
• Copper-silver ionization (continuous)
• Chlorine Dioxide (ClO2)• Monochloramine• Point-of-use filtration
© Special Pathogens Laboratory
Multiple Approaches
BUILDING 1• High percentage of
outlets positive with cases;
• monochloramine system installed
BUILDING 2• High percentage of
outlets positive no cases;
• copper-silver ionization system installed
© Special Pathogens Laboratory
0%
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60%
80%
100%
120%
Dis
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Building 1 - Legionella Distal Site Positivity Reduction With Monochloramine
Distal Site Positivity
Monochloramine Start Date
© Special Pathogens Laboratory
© Special Pathogens Laboratory
Conclusions
• Both disinfection approaches were effective in reducing Legionella positivity
• Monochloramine was used in the building housing the highest risk group and to achieve the fastest reduction
• Legionella remediation - not “one size fits all”
© Special Pathogens Laboratory
Monochloramine Field Evaluation
© Special Pathogens Laboratory
PROTECTING TRANSPLANT, HIGH RISK PATIENTS, NEONATES
We Filter the Air…But Let Them Drink Tap Water?
© Special Pathogens Laboratory
Pediatric Legionnaires’ Disease
• CDC study showed 72% pediatric cases had healthcare exposure
• Mortality rate 22%
© Special Pathogens Laboratory
Protect Vulnerable Populations with Point Of Use Filters
© Special Pathogens Laboratory
My First Field Evaluation
American Journal of Infection Control 2005; 33:S20-25.
© Special Pathogens Laboratory
History of Point-of-Use Filters
• Bacterial exclusion at 0.2 micro
• Use duration has gone from 15 days, to 31 to 62 and beyond
• Depending on water quality (particulates), filters may clog
• Seen significant improvement
© Special Pathogens Laboratory
2013 Study Using POU Filters
• Newer Products – up to 62 days of use• Test Location – Cancer Center• Sampling – five control faucets (no filter)
and five test faucets (with filters)• Sampling Frequency– Weekly• Duration – 14 weeks
© Special Pathogens Laboratory
POU Filters Eliminate Legionella
© Special Pathogens Laboratory
Evaluation Published in AJIC
American Journal of Infection Control 2014: 42; 1193-6.
© Special Pathogens Laboratory
Aqua-Tools: Point-of-Use Filters
• Our evaluation of 62 day filters Study No. 1 performed at a 1,157 bed
healthcare facility (faucet filters) - completed Study No. 2 at a 200 bed community
healthcare center (faucet and shower filters) –ongoing Results presented separately today…
© Special Pathogens Laboratory
Study Design for POU Filters
• Test Location – Hospital• Sampling – five control outlets (no filter)
and five test outlets (with filters)• Sampling Frequency– Weekly• Duration – at least 12 weeks
© Special Pathogens Laboratory
Point-of-Use Filters: Conclusions
• System-wide disinfection not always the best answer
• Next generation filters last longer—more than 60 days
• High risk areas may require long-term use for maximum risk reduction
• Extend protection to home for high risk patients?
© Special Pathogens Laboratory
Journal Am Water Works Assoc 2014; 106(10): 24-32
Disinfection Method Review
© Special Pathogens Laboratory
EPA Issues Review of LegionellaControl & Disinfection Methods
© Special Pathogens Laboratory
U.S. Regulatory Agencies: New Focus
on Legionella Prevention
© Special Pathogens Laboratory
CDC Focus:Effective water management
for Legionnaires’ disease prevention
© Special Pathogens Laboratory
CDC
© Special Pathogens Laboratory
Conclusions• Missed prevention opportunities leads to
outbreaks
• Making water management programs a routine part of building ownership and management will require education and enforcement
© Special Pathogens Laboratory
NSF International & ASHRAE Collaborate
© Special Pathogens Laboratory
NSF 444: Prevention of Injury
and Disease Associated with Building Water Systems
© Special Pathogens Laboratory
© Special Pathogens Laboratory
Klebsiella oxytoca, Enterobacter cloacae, Pseudomonas aeruginosa
Water From MICU faucet!
What Culture Shows
© Special Pathogens Laboratory
Not Just Legionella in Our Water Faucets
Acinetobacter
P. aeruginosa
S. maltophilia
Amoeba Resistant Microorganisms ( NTM’s )
© Special Pathogens Laboratory
Nontuberculous Mycobacteria
Clinical Infectious Diseases 2015;61(1):67–75
© Special Pathogens Laboratory
Sorin 3T Heater Cooler Unit
Our Testing of Sorin Instruments
• We tested 92 Sorin instruments from 20 hospitals in 13 states
• 42.2% were colonized with M. chimaera
• Some instruments were colonized with as many as 4 NTM species
• HPC values on some instruments were as high as 5,200,000 cfu/mL
© Special Pathogens Laboratory
Positive Sorin Culture
M. chimaera
© Special Pathogens Laboratory
Experience
© Special Pathogens Laboratory
Learn From Other’s Mistakes
• Outbreaks, water service disruption and construction Don’t risk it – test now! Renovation and construction conditions
favor LegionellaoInstallation of low flow/electronic sensor
faucetsoLong dormant periods before occupying
Summary
• Legionnaires’ disease is increasing• Potable Water systems, especially in
hospitals (and other buildings) with complex hot water systems, are the most important source of Legionellatransmission.
• Proactive prevention = ASHRAE 188 Water Management Programs and Risk Assessments
• Environmental testing for Legionella is a key indicator for disease risk
Legionella Anxiety?
© Special Pathogens Laboratory
MEDICATION
© Special Pathogens Laboratory
Dr. Stout’s Legionella Chill Pills
• For treatment of Legionella-related anxiety.
• Take 2 tablets 1 hour before Legionella testing or as needed.
© Special Pathogens Laboratory
Mission: End Legionnaires’ Disease
• No one should die from a preventable disease caused by a bacteria in water.
• Legionnaires’ disease can and should be prevented.
© Special Pathogens Laboratory
Let’s End LD Together
© Special Pathogens Laboratory WWW.SPECIALPATHOGENSLAB.COM
THANK YOUDr. Janet E. StoutPresident, Microbiologist