legionella investigations in coloradolegionnaires’ disease • severe form of pneumonia • not...
TRANSCRIPT
Legionella Investigations
in Colorado
Tori Burket, MS, CPO
Nisha Alden, MPH
Introductions
Tori Burket, MS, CPO
Waterborne Disease Epidemiologist
Colorado Department of Public Health & Environment
Nisha Alden, MPH
Active Bacterial Core & Influenza Surveillance Manager
Colorado Department of Public Health & Environment
1. Legionella background
2. Case and Outbreak Investigation protocol
3. Prevention in healthcare facilities
4. Example Outbreaks
5. Conclusions & Questions
Agenda
Legionella
• Bacterium
• Naturally found in many sources of fresh water
Reservoirs, ponds, pools, hot springs,
municipal water systems, ice machines,
cooling towers, and more
• Causes Legionnaires’ disease
Spread through inhalation of contaminated
aerosolized water droplets
• Shown to survive between ~32o F - 158
oF
Grows and multiplies between ~68oF - 128
oF
1
Legionnaires’ Disease
• Severe form of pneumonia
• Not spread from person to person
• Symptoms usually appear 2-10 days after exposure
Shortness of breath, cough, fever,
headache, muscle ache, altered mental
status
• People most at-risk
Over the age of 50, immunocompromised,
history of smoking, pre-existing respiratory
illness
• In Colorado, between 2007-2016
~92% hospitalization rate
~8% fatality rate
2
Legionellosis Disease
Investigation
1. Legionellosis case is reported to CDPHE within 4
days of positive laboratory results
2. Case patient is typically interviewed within 7 days
of received report (aim for within 3 days)
3. Environmental exposures are noted and cross-
checked against other cases within the last year
Routine Steps
When is an environmental
investigation conducted?
1. One case likely associated with a healthcare facility
• Case spent the majority or entirety of their
exposure period in a healthcare facility
2. Two or more cases associated with the same
exposure within 1 year
• Examples include hotels, pools/hot tubs, gyms, hot springs,
retirement homes, and healthcare facilities
Environmental Investigation
Protocol
1. Water and/or HVAC restrictions
2. Environmental investigation
3. Mitigation recommendations
4. Retrospective and prospective surveillance
Water Restrictions
1. Discontinue use of non-vital water features that the
public has access to, such as:
Water fountains, sinks, ice machines, hydrotherapy
tubs, pools/hot tubs, saunas…etc
2. Avoid using showers if possible
Recommend utilization of bed/sponge baths
3. Bottled water usage
Dependent upon level of risk
To reduce further risk of illness until mitigation can be completed
Environmental Investigation
Environmental Assessment
• Facility wide assessment to identify:
Water/HVAC features and sources
Building and water/HVAC system design
Current water management plan practices
Previous or current disruptions/maintenance
to the water/HVAC system
Infection control practices
Environmental Investigation
Environmental Sampling
• Water samples and swabs analyzed from identified sources
• Water chemistry levels analyzed from identified sources
What is a Biofilm?
A group of microorganisms in which cells stick to
each other and produce an slimy protective surface
Mitigation Strategies:
Potable Water Systems
Immediate Remediation Methods
• Drain and flush water heaters to
reduce sediment accumulation
• Flush water entire water system,
including each outlet (showers and
sinks), to eliminate stagnant water
• Clean and disinfect water features
with chlorine bleach solution (50
mg/L) to remove biofilm
Mitigation Strategies
Water System Disinfection
• Superheating: Raise
temperature of water heaters
to 160o-170
oF and flush each
outlet for a minimum of 5
minutes
• Hyperchlorination: Raise level
of chlorine to a minimum of
2ppm and leave in system for a
minimum of 2 hours followed by
a system flushing
Mitigation Strategies:
Pool/Hot Tub
1. Drain hot tub (can drain pool if able to)
2. Scrub all hot tub and pool surfaces, skimming devices,
jets, and circulation components with disinfectant
3. Replace filter media and service filter unit(s)
4. Inspect for and fix broken or poorly functioning
components
5. Refill and superhalogenate water in hot tub and pool
Follow-Up Testing6 month re-testing schedule
• Sampling every 2 weeks for 3 months and then
• Sampling once a month for 3 months
Conditions for re-opening/lifting restrictions
• Completion of mitigation requirements
• Negative Legionella culture test results
• Pass inspection (for pools/hot tubs)
Conditions for closure
• Any positive Legionella culture test results
• Fail inspection (for pools/hot tubs)
9
Surveillance Recommendations
for Healthcare Facilities
Retrospective Surveillance
1. Review records of patients from the last 6-12 months to find
those diagnosed with pneumonia while in or within 10 days of
leaving the facility
2. Identify if these patients were tested for Legionella
Prospective Surveillance
1. For the 3 months following remediation, patients that develop
pneumonia should be tested for Legionella using a sputum
culture and UAT
2. Clinicians ordering diagnostic testing will need to be notified of
this recommendation
Prevention of legionella
in the water system
Implement and utilize a water management plan!
CMS Regulation Goal:
Reduce the Risk of Growth & Spread
of Pathogens Requirement
CMS Regulation Requirements
1. Conduct facility risk assessment to identify where Legionella
could grow and spread in the facility water system
2. Implement a water management plan that considers ASHRAE
industry standard and the CDC toolkit, and includes control
measures such as physical controls, temperature
management, disinfectant level control, visual inspections,
and environmental testing for pathogens
3. Specify testing protocols and acceptable ranges for control
measures, and document the results of testing and corrective
actions taken when control limits are not maintained
Colorado Outbreaks
10
Outbreak: LTCF A
• Single case of legionellosis in a skilled nursing facility in
metro-area
• Testing conducted in potable water system
• PCR positives during initial sampling
• Legionella pneumophila- hot water return, water
feature, patient room shower swab
• Legionella spp- patient room shower water, patient
room shower swab, water fountain, lobby sink
• 10 days between initial sampling and repeat sampling
• Superheating occurred very quickly
• All follow-up sampling was negative
Outbreak: Hotel B
Locally owned franchise hotel in southeastern Colorado
• Five cases of unexplained pneumonia in guests who
attended a wedding at the hotel at the end of July
Three of the five cases were hospitalized and developed
severe manifestations of their illness
15
Hotel B Sampling
Potable Water System (16)
• Water heaters (3)
1 liter samples
• Guest room showers (6)
1 liter samples
Swabs
• Guest room sinks (6)
1 liter samples
Swabs
• Ice machine (1)
Swabs
Pool/Hot Tub (10)
• Pool (7)
Water, water line,
filter baskets,
pump, filter
• Hot tub (3)
Jets, filter, pump
Swamp Coolers (2)
• 1 liter samples (2)
16
Hotel B Findings
Swamp Coolers
Dead bird inside one of the chillers
Rough shape; leaks, cracks, sediment…etc
Detected dead Legionella
Pool/Hot Tub
Pool hadn’t been drained in 5 years
Chemical levels were way off
Filter media hadn’t been replaced in quite a while
No CPO on staff
No records being kept
Detected both live and dead Legionella
Potable Water System
Problems with water heaters and water temperature
Brown water came out of one of the showers
Detected dead Legionella
17
Conclusions
1. Investigations are lengthy, frustrating, and expensive
2. Hotels & LTCFs pose unique risks to public health, so
extra measures are needed to ensure safety
3. Prevention is cheaper and easier than responding to an
outbreak
17
Questions?