Legionnaires' Disease: A Preventable Disease

© Special Pathogens Laboratory
Janet E. Stout, PhD
President & Director
LEGIONNAIRES’
DISEASE
A Preventable Disease

My Affiliations
• President & Director
Special Pathogens Laboratory, Pittsburgh, Pa.
• SPL is “More Than a Lab”
• Research Associate Professor, University of
Pittsburgh Swanson School of Engineering
Department of Civil & Environmental
Engineering
• Research on Legionella control strategies

Today’s Topics
• Understanding Legionella In The Built
Environment
• Role of Legionella Testing In Disease
Prevention
• NY Regs & ASHRAE Standard 188
• Approaches To Prevention

Celebrating More Than 40
Years of Making Headlines

Things That Happened in
1976 in Philadelphia
40 years is a long time!

American Legion Convention
at the Bellevue-Stratford Hotel

1976 Philadelphia
• 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

1980: Research Begins in Pittsburgh
• More than 30
years studying
Legionnaires’
disease
 I’m a
Legionellologist

Research Pioneers Starting in 1982
• Over 100 nosocomial
cases identified in 5
years in one hospital
• An epidemic redefined -
endemic disease
• The source was the
hospital water system –
not a cooling tower!
Janet E. Stout and Victor L. Yu

• NOT a common
source for
sporadic and
hospital-acquired
cases
• More commonly
associated
with large
community
outbreaks
Paradigm Shift: Not Cooling Towers

What We Know Now
Potable water especially in hospitals
(and other buildings)
with complex hot water systems,
is the most important source of
Legionella transmission.

A HIGHLY SUCCESSFUL
MICROBE
Legionella

Measures of Success
• Numbers up?
• In the news?
• Famous people talking about you?
• Getting too famous – industry and
government agencies after you?

Successful Microbe: Disease
Incidence Increasing?

Consider This…
• Legionellosis cases have increased
substantially – over 200% in last 10 years

Who’s At Risk
• Elderly
• Smokers
• Immunocompromised
 Transplant patients
 High-dose steroids for lung disease
 Diabetes
 Cancer
• Approx. 25% cases no known risk factors

Centers for Disease Control
and Prevention Statistics
• 77% >50 years
• 62% male
• Hospitalizations occurred in 98%
 ICU admission in 39%
 Death in 10%–30%

Legionnaires’ Disease in Hospitals
• 35% of reported cases met the case
definition for hospital-acquired infection
(range 45%–25%)
• Case fatality rate was 28%
(range 46%–14%)
From Benin A.L., Benson R.F., Besser R.E. Clin Infect Dis 2002; 35:1039-46. Data
reported to the CDC from 1980-1998.

Cases Linked to Water Systems
• Warm water
distribution in:
 Hospitals
 Nursing homes
 Rehabilitation
centers
 Office buildings
 Apartment
buildings
 Hotels
• Other water
systems:
 Spas and hot tubs
 Decorative
fountains
 Humidifiers
 Cooling towers

HEALTHCARE-ACQUIRED
CASES
Epidemiology and
Infection Prevention

Many Cases Still Missed
• Diagnostic tests for Legionella not
routine – often not done
• Many studies have demonstrated
under reporting/missed diagnosis

Under Reporting
Due to Missed Diagnosis

Results for 37 Cases
41% of Legionella cases were missed
following current IDSA-ATS
recommendations for Legionella
testing

Urinary Antigen:
the Primary Diagnostic Method
• Urine antigen primary method of diagnosis
in 97% of cases
• Culture of Legionella from respiratory
secretions (sputum) in only 5% of cases
• Early diagnosis and treatment = better
outcome
MMWR 2011 Vol 60 (32)

Dangers of Dependency on Urine
Antigen Testing for Diagnosis
• Urine antigen specific for
L. pneumophila, serogroup 1 only
• If used to screen for healthcare-
acquired LD, you’d better know
what’s in your water!
 If Lp-6 in the water, diagnosis will be
missed
MMWR 2011 Vol 60 (32)

Transmission by CPAP?

PREVENTING
LEGIONNAIRES’ DISEASE
Is It Worth The Effort?

Legionnaires’ Disease
• In the U.S. approximately 600,000
adults are diagnosed with
community-acquired pneumonia
requiring hospitalization
• 2-5% are caused by Legionella, as
many as 30,000 cases/year

Annual Healthcare Costs From
• Total hospitalization costs
$101 - $321 million dollars
per year
• Assumption 10 day stay and
$34,000 per patient
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.

Legionellosis in the U.S.
Outbreaks
continue to occur
(building warm
water systems,
cooling towers,
fountains)

Outbreaks 2000 to 2014

Hospitals at Significant
Risk According to Recent
CDC Report
Legionella in hospitals –
accounted for 57% of all
cases and 85% of deaths

Measures of Success
Increasing ratings?
In the news?
• Famous people talking about you?
• Getting too famous – industry and

Outbreaks in Nursing Homes
& Assisted Living Facilities

HOSPITAL OUTBREAK LINKED
TO NEW CONSTRUCTION

South Bronx Outbreak
• 130 cases, 12
deaths
• Declared over
August 20,
2015

Outbreak Linked to Hotel
Cooling Tower

NEW YORK STATE
EMERGENCY REGULATIONS

Emergency Regulation
• Cooling towers must
be registered
• Legionella testing
every 90 days
• Inspection
• Certification
• Maintenance program

I Love New York!

Outbreaks Worldwide

Outbreak
• Catalonia, Spain
 113 cases, caused by Legionella
pneumophila, serogroup 1
 13 cooling towers tested
 DNA subtype of isolates from one tower
matched the subtype of 10 patient isolates
implicating it as the outbreak source

More Outbreaks: 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

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.”

HEALTHCARE-ACQUIRED LD
Approaches To Prevention

Denial
Most wait to
address
the problem until
after
a case of
Legionnaires’
disease
is diagnosed.

Legionella Testing
If you don’t look for
it, you won’t find it.
If you don’t find it,
you don’t think
you have a problem.
If you don’t think
you have a problem,
you don’t do anything
about it.
−Bruce Dixon, M.D.
Director, Pittsburgh ACHD

CDC Changes Position on Testing
“We are not against testing water for the
presence of Legionella…
We think it has its place, particularly in
healthcare facilities.”
Cynthia Whitney, MD, Division of Bacterial Diseases, National Center for
Immunization and Respiratory Diseases, CDC. June 8, 2016 Pittsburgh Post Gazette

Approaches to Prevention
• REACTIVE
 After 1 transplant
patient or 2+ cases
within 6 months
• Combined
epidemiologic and
environmental
investigation
• Legionella source
identified =
decontaminate
• PROACTIVE
 Before cases, perform
environmental
surveillance
 Also perform clinical
surveillance to identify
unrecognized cases
• Legionella source
identified =
decontaminate

Proactive Approach Reduced
Am. J. Infection Control 2005; 33(6):360-367

Pittsburgh Proactive Approach
Culture hot water systems.
Was Legionella found?
Prior cases of legionellosis observed?
Colonization of distal sites >30%?
Prospective clinical
surveillance detected
legionellosis?
Consider Secondary
Disinfection
Continue Environmental
Surveillance
YES NO
YES NO
YES NO
YES NO
Reference:
Approaches to
Prevention and
Control of Legionella
Infection in Allegheny
County Health Care
Facilities. 1997.

Study Findings
• Reviewed 487 reported cases from
1991-2001 (Pre- and-post guideline)
• Proportion of cases hospital-acquired:
 Pre-guideline = 33%
 Post-guideline = 9%
• Significant decrease in the post
guideline period (p<0.0001)

Our Study Results of 48 Hospitals
• Proportion of hospitals performing
environmental surveillance = 65%
• Proportion that started water
treatment (disinfection) = 44%

I Love New York!
New York Is being Proactive!
State-wide
regulation
requires testing and
water management
plans for cooling
towers
AND
potable water
systems of
healthcare facilities

Table at www.specialpathogenslab.com

Legionella Prevention In New York:
Cooling Towers AND Healthcare
• First Regulation in the U.S.
 Addition of Part 4 to Title 10 of the Official
Compilation of Codes, Rules and Regulations of
the State of New York
(Protection Against Legionella)
• This Subpart addresses Legionella
exposure in general hospitals and
residential health care facilities (collectively,
“covered facilities”).

New NY State Regulation
For Legionella Prevention
• Requires that all covered healthcare
facilities adopt and implement:
 a sampling and management plan for
their potable water systems by
December 1, 2016, and
 new covered facilities must adopt such
plan prior to providing services.

Percentage of Positive
Legionella test Sites Response
<30%
Maintain environmental assessment and
Legionella monitoring in accordance with the
sampling and management plan
>30%
Institute short-term control measures and
notify the department.
• Re-sample no sooner than 7 days
and no later than 4 weeks after disinfection
• If retest is ≥ 30% positive, repeat
short-term control measures.
• If results < 30% positive, resume
monitoring in accordance with the
sampling and management plan.
Interpretation of Routine Legionella
Culture Results from Covered Facilities

Where Did The 30%
Target Come From?

Evidence-based Origins of 30% Distal
Site Positivity As Risk Indicator

Correlation Between Disease and
Distal Site Positivity
• Whenever monthly site positivity
exceeded 30%, cases of
Legionnaires’ disease appeared in
those months.
• Similarly, when positivity fell to 20%
or less, no case of disease were
observed.

Proportion Not Concentration
Risk of Legionnaires’ disease was better
predicted by the
proportion
of water system sites
testing positive for Legionella
than by the
concentration of Legionella bacteria.
Kool J L, et al. Infect. Control Hosp. Epid. 1999 20:797-805

Validated in a Multi-Center Study
Infect Control Hosp Epid 2007; 28 (7)

0%
20%
40%
60%
80%
100%
120%
DistalSitePositvity
Date
High (>30%) Legionella Distal Site Positivity And
Cases Prior to Treatment
Distal Site Positivity
No Cases after
Treatment (NH2Cl)
Cases

Where You Can Find Legionella
• Building (warm)
water systems
 Faucets, showers
 Hot water tanks
 Decorative fountains
 Pools, spas
 Cooling towers
 Ice Machines

You Can’t Tell by Looking
>3000 CFU/mL
Legionella pneumophila
serogroup 1
Automated dosing of
chemical biocides
and clean

Microbiological Testing: HPC (Total) Bacteria
Does An HPC Test Predict A Problem
With Legionella?

Heterotrophic Plate
Count (HPC) Bacteria Testing
• Bacteriological indicator … estimates
microbial content in the circulating
water of a cooling tower system, such
as heterotrophic plate count (HPC) as
measured in a water sample or by a
dip slide.

Heterotrophic Plate
What do you learn?
• HPC method does not detect Legionella
• HPC cannot be used to predict presence
or absence of Legionella
• HPC counts can be low when Legionella
is high

2015 Publication

Heterotrophic Plate
HPC or ATP Test Can:
• Be used as a biocide performance
indicator for general microbiological
fouling
• Be an inexpensive early warning of a
process or biocide application upset

NYC HPC Test NYS HPC Test
Weekly bacteriological
sampling and analysis
using dip slides or
heterotrophic plate
counts (HPC).
Monthly bacteriological
sampling and analysis
using dip slides or
heterotrophic plate counts
(HPC).
Result & Response Result & Response
CFU/mL < 10,000
maintain program
>10,000 and <100,000;
Initiate immediate
disinfection
(See Table 8-2 for details)
Not Specified

Legionella Test Result
(CFU/mL) Response
Not Detected
(<20 CFU/mL)
Maintain treatment program and Legionella
monitoring in accordance with the
maintenance program and management plan
For levels at ≥ 20
CFU/mL but < 1000
CFU/mL perform the
following:
Review treatment program.
• Institute immediate online disinfection
Retest the water in 3 – 7 days until one
sample result is < 20 CFU/mL. If retest is ≥
20 CFU/mL but < 100 CFU/mL, repeat
online disinfection and retest until < 20
CFU/mL attained.
• If retest is ≥100 CFU/mL but < 1000
CFU/mL, further investigate and
immediately perform online disinfection.
Retest until < 20 CFU/mL attained.
• If retest is ≥ 1000 CFU/mL, undertake
control strategy and notifications
Guidance for Cooling Towers In NYS

Risk Assessment and
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

Meaning for You
Sampling the water system of a
building can give you a meaningful
“snapshot” of the colonization status.

Legionella Testing
• Legionella testing can verify
the performance of water
treatment & water safety plans

Did You Know CDC Has a
New Position On Testing?
“We are not against testing”
water for the presence of
Legionella…We think it has its
place, particularly in healthcare
facilities.”
Cynthia Whitney, MD Division of Bacterial Diseases, National Center for Immunization
and Respiratory Diseases, CDC. June 8, 2016 Pittsburgh Post Gazette

Is the Sky Falling?
If I Find Some Legionella?

What is an
acceptable amount
of
Legionella?

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IS ZERO
NECESSARY?

Zero Legionella is
virtually impossible to
achieve in complex
water systems
Don’t Chase Zero

Preventing Legionnaires’ Disease
• Controlling Legionella is about
preventing disease not about
reaching zero Legionella in water.
• Zero Cases Is the Goal

AN INSIDE LOOK AT
LEGIONELLA

Legionella Colony Morphology
Colonies of Legionella pneumophila have a typical
ground-glass, opalescent morphology

Not All Legionella Are Dangerous

Auto fluorescing Legionella Species:
Uncommon Disease-causing Agent
Some species show blue-white extracellular fluorescence
Under long wave ultra-violet light

Legionella Culture Isolation
• These species include
L. anisa, L. bozemannii
L. dumoffii, L. gormanii,
L. erythra and L
rubrilucens

Labs Vary in Culture Methods for
Legionella Testing & Identification
Apples to apples or apples to oranges?

Did you know that labs
differ in their methods for
Legionella testing &
identification?
ELITE Certified Laboratories

• Methods for Legionella detection and
quantitation
 Standard culture – validated/gold
standard
 Non-culture based molecular methods
• Quantitative Polymerase Chain Reaction
(qPCR)
• Molecular/Sequencing (NGS, WGS)
Detection of Legionella

Culture Method
• Industry standard/best practice
 Standards based
• ISO 11731 (1&2)
• ASTM D 5952
• CDC
• International – HSE L8 ACP 2013
 Laboratory Proficiency Programs
• NY ELAP
• ELITE is not a traditional proficiency program

Labs Use Different Culture Methods
• Labs use all or only some of these
processing methods
 Pretreatment (heat and/or acid)
 Filtration (yes/no or how much)
 Special culture media (types and how
many)
• Labs provide limited identification (ID)
 Only presumptive agglutination test?
 Definitive ID with DFA or sequencing for
unusual species?

Legionella Identification
• Suspected Legionella
isolates are confirmed
by either slide
agglutination or by
direct fluorescent
antibody staining
• Latex agglutination for
L. pneumophila
serogroups 1, 2-14
and Legionella
species.
Oxoid Latex agglutination

• Used for
definitive
identification of
Legionella after
isolation by
culture
Fluorescent Antibody Stain

Patient isolates compared to environmental isolates
using PFGE (Pulsed-field Gel Electrophoresis).
Cultured Legionella
“Fingerprinted” by DNA Typing

NYC Specifies Culture Method
• Labs testing samples from NY must
use International Organization for
Standardization (ISO) Legionella
culture methods:
 Enumeration of Legionella (ISO 11731)
or International Standard Method 11731-
2 Water quality detection and
enumeration of Legionella

NY State Specifies Culture Method
• All Legionella culture analyses must
be performed by a laboratory that is
approved to perform such analysis by
the New York State Environmental
Laboratory Approval Program (ELAP).

Confirm Lab Meets Requirements
• Labs performing
testing should be
 Accredited for
microbiology testing,
quality (ISO 17025)
and for Legionella
testing as a specific
field of testing
 Not just CDC ELITE
certified

SPL - Most
accurate
results are
obtained
when all
steps are
performed

Accreditation & Certification

FAMOUS PEOPLE TALKING
ABOUT YOU
Successful Legionella

Erin Brockovich & Legionella?
• Draws attention to the
release of a report
that said
Legionnaires’ disease
cases are on the rise
in New York because
of poor enforcement
of clean water
regulations.

Hollywood Walk of Fame
for Legionella?

Measures of Success
Increasing ratings?
In the news?
Famous people talking about you?
Getting too famous – industry and

Legionella Has Their Attention
• ASHRAE
• CDC
• EPA
• NSF
• WRF
• Industry
Organizations AWT
and CTI

• First Legionella
standard in the
United States.
• Approved
June 26, 2015

Risk Management Process

Purpose of ASHRAE Standard 188
Establish minimum Legionellosis risk
management requirements for building
water systems.

The Real Purpose of
ASHRAE Standard 188
To help
engineers and
infection
preventionists
communicate
more effectively

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.

The Team
• Titles
 Administrator
 Facilities manager
 Infection control
 Water treatment
professional
 Risk manager/adjuster
 Legionella consultant
• Abilities
 Power to make
decisions
 Understanding of facility
 Knowledge of water
systems
 Ability assess facility risk
tolerance
 Expertise in Legionella

SPL’s 5 Steps to a Legionella
Water Safety Plan
1. Pre-Assessment information
2. Pre-assessment water safety team
meeting/call
3. Onsite assessment
4. Baseline data assessment report
5. Water safety plan

Fundamentals for
Legionella Water Safety
• Know who is at risk for Legionnaires’ disease
in your facility
 Highest risk: smokers, elderly and immune
suppressed
 But, can affect those with no risk factors
• Identify key players who are responsible for
water safety
 Facility managers, maintenance, occupants,
regulators, engineers, water treatment
providers, Legionella experts, etc.

Legionella Water Safety
• Know what part of a water system could lead
to Legionella exposure
 Highest risk: Hot potable water systems
 Not all buildings have Legionella
 Risk is a function of
• susceptibility of occupants
• extent of colonization or exposure
• pathogenicity of Legionella species

ASHRAE 188: Mind the Gaps

ASHRAE Compliance
• Compliance is just
the first step to
protect yourself
and building
occupants
• Compliance
doesn’t guarantee
Legionella control
and cases can
occur.

ASHRAE 188:
Your Decisions Fill The Gaps

ASHRAE 188 Compliance
Good 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

Team Determines Approach to
Testing And Disinfection
• The Program Team shall determine
the testing approach including:
 Sampling frequency
 Number of samples
 Locations and sampling methods

Knowledge
The Program Team shall have knowledge
of the building water system design
and water management as
it relates to Legionellosis

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 (HPC or ATP) are controlled,
Legionella is controlled.
• Water and energy conservation approaches
minimize Legionella risk.
• Legionella is not a concern during construction.

CDC Focuses on
Effective Water
Management For
Prevention

DISINFECTION APPROACHES
I Have Legionella in My Building…
Now What?

DISINFECTION OPTIONS

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
chlorination (2-4 mg/L)
• Copper-silver
ionization (continuous
and short-course)
• Chlorine Dioxide
(ClO2)
• Monochloramine
• Point-of-use filtration

Short-term Disinfection Is
Whack-a-Mole

PROTECTING TRANSPLANT,
HIGH RISK PATIENTS, NEONATES
We Filter the Air…
But Let Them Drink Tap Water?

Water is a Source
of
infection
especially for
high risk patients –including
neonates

Healthcare-acquired Pediatric LD
• CDC study showed
72% pediatric
cases had
healthcare
exposure
• Mortality rate 22%
Alexander NT, et al 2008
ICAAC

Fatal Water Birth
E, Sanyal K, Threadgill H, Cervantes D. Fatal legionellosis after water
birth, Texas, USA, 2014. Emerg Infect Dis. 2015 Jan].

Point-of-Use Filtration
• High Risk Patients
• Bone marrow and
solid organ transplant
units
• Hematology/
oncology units
• NICU

Field Evaluation
AJIC 2014; 42: 1193-1196

Point-of-Use Filters: Conclusions
• System-wide disinfection may not always
be 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?

Journal Am Water Works Assoc 2014; 106(10): 24-32
Review of Methods

EPA Issues Review of Legionella
Control & Disinfection Methods

Acinetobacter
Pseudomonas
aeruginosa
S. maltophilia
Amoeba Resistant Microorganisms
(Mycobacteria )
Not Just Legionella in
Our Faucets

Culture Shows Pathogens
Klebsiella oxytoca and
Enterobacter cloacae
Pseudomonas aeruginosa

See You in Portland - APIC 2017
• 1401/1402 - Water and Healthcare-Associated
Infections: The Importance of Developing and
Implementing a Water Management Plan
• Presenters: Janet E. Stout & Matthew Arduino
• Wednesday, June 14, 2017
• 3:00 PM – 5:30 PM

PREVENTING
LEGIONNAIRES’
DISEASE
How are we doing?

Progress Has Been Slow…
Really Slow!

Total Legionella Control
An evidence-based,
integrated platform of
solutions:
• Legionella &
Pathogen Testing
• Consulting &
Education
• ZEROutbreak
Protection

Our 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.

WWW.SPECIALPATHOGENSLAB.COM
THANK YOU
Dr. Janet E. Stout
President, Microbiologist
info@specialpathogenslab.com

Legionnaires' Disease: A Preventable Disease

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Legionnaires' Disease: A Preventable Disease