Water Bacteria and Infection Prevention Andrew Streifel - - PowerPoint PPT Presentation

Water Bacteria and Infection Prevention

Andrew Streifel Environmental Health & Safety University of Minnesota strei001@umn.edu

Levels of Risk

Healthy person

• Chronic obstructive pulmonary disease
• Diabetes
• Steroids
• Cancer - solid tumor
• HIV infection-end stage of spectrum
• Organ transplant

– Kidney/heart – Lung/liver

• Malignancy - leukemia/lymphoma

Bone marrow transplant (BMT) allograft

Greatest risk

Legionellosis from MMWR

2013 (Up to Dec. 28) 2012 (Up to Dec. 28)

Massachusetts 185 173 Illinois 265 226 Maryland 145 123 Minnesota 24 51 Arizona 49 44 Pennsylvania 419 300 Florida 254 213 South Carolina 20 26 USA 4548 3688

Hospital Tap Water & Infection Prevention

US Hospitals Yearly: 1.7 million infections; 99,000 deaths Pseudomonas aeruginosa alone: 1,400 deaths in US Problem: Waterborne pathogens such as Legionella, adapted to life in a relatively nutrient-poor environment, may be hard to culture using a nutrient-rich environment for 24-48 hours at 37°C. Solution: Use special media (e.g., R2A) for 14-28 days at 25°C. Cervia, et al, A Reservoir of Risk for Health Care-Associated Infection, Infect Dis Clin Pract 2008;16:349-353

Common heterotrophic plate count bacteria

Municipal Water Quality

• Debris & color
• Bacteria (DWS <1cfu/100ml coliform)
• Minimal fungi & virus (DWS <500cfu/ml - HPC)
• Residual disinfectant
• Water usage source for:

– Drinking – Dialysis – Laboratory – Process

While the majority of US population gets their drinking water from surface water the most common source of drinking water in the US is a well.

Water Quality Parameters

Well Water Surface Water

Reservoir River Mineral Content High Variable Seasonal Organic Content Low Variable

Depth Dependent

Variable

Seasonal

Chlorination Free Available Free/Combined Combined Bacteria Low Variable Seasonal PH Stable Stable Variable Ability to be treated Stable Seasonal Variable

Advantages of Well Water in Hospital

• stable water source does not change content quickly
• cheap water source after initial cost
• can be local depending on depth of well
• few microbes
• emergency water supply
• no chlorine

Disadvantages of Well Water in Hospital

• high mineral content may require added treatment like softening
• may stain depending on presence of iron or other minerals
• must pay for waste water discharge and permit
• may require chlorine that oxidize metals to be carbon filtered
• may be affected by other wells during periods of high usage or drought

• Coagulation
• Chlorine/Ammonia

Primary Secondary

• Chlorine/Ammonia
• Polyphosphate
• Fluoride

Tertiary

• KMNO3
• Coagulation
• Lime

Minneapolis MN

Waterborne Infections

• Many cases cited
• Causes vary
• Single case vs. outbreak
• Distinguish healthcare

associated (nosocomial) from community acquired infection

– Determine source: supply vs. healthcare facility vs. reservoir

• Many unrecognized cases
• Biofilms protect & insulate

Biofilm development from planktonic to sessile colonies

Biofilm thrives in stagnant water

Waterborne Pathogens a Public Health Risk in U.S. Hospitals AWWA – Jan. 2012

• Survey of 192 Hospitals

around the United States:

• All had at least one Case of

Legionnaires’ Disease.

• 16% Had more than five

cases

• 60% had capability to test

for Legionella – but only 21% had a routine Protocol for testing.

Healthcare-associated Outbreaks of Legionellosis

• Contaminated aerosols
• Exposure to waterborne bacteria in:

– Cooling towers – Showers, aerators – Faucets – Ice machines – Respiratory therapy equipment – Room-air humidifiers – Decorative fountains

Healthcare Acquired Legionellosis from Fountains

NIH-2008 2 BMT pts

• 30 month old fountain
• stagnation of water during 4 month outage before usage
• contamination despite ozone and filtration
• routine maintenance being conducted
• false negative sample results
• sampling error
• inadequate culture techniques from commercial lab

Wisconsin-2010

• 8 outpatients affected
• 9 of 44 environmental samples positive 20%
• support foam most contaminated
• 8 positive cultures from fountain
• glass wall, ionization disinfection
• maintenance, testing and more measures still there was contamination
• supplemental disinfection with ionization did not help

Issues: foam and heat from lights

Water feature risk analysis

Low aerosol production Enclosed cascade Water wall Aerosol producers Spray Mist

An Outbreak of Legionnaires Disease Associated with a Decorative Water Wall Fountain in a Hospital Haupt, TE. et al, Infect Control Hôpital Epidemiology 2012;33(2):185-191

Biofilm development is enhanced when:

• temperature is >68F
• submerged lighting is present
• nutrients
• water feature materials support growth
• water flow slow or stagnant
• aerosol generation

Water treatment

• size of fountain
• ozone
• halogens
• chlorine dioxide
• UV

WATER FEATURES CAN BE THE SOURCE OF EXPOSURE

Waterless Fountain University of Minnesota Medical Center

FGI Guidelines for Design and Construction of Hospitals ……. 2014 “Installation of indoor, unsealed open water fountains shall not be permitted”

Water Considerations

• Source water

– Well or surface

• Hot water plan

– Instantaneous – Mixing valves – Expansion tanks

• Pipe material
• Backflow preventers
• Construction

– Pipe storage – Avoid stagnation

Plumbing Component Considerations

• Hot water heaters (instantaneous)
• Pipe material (galvanized, copper, plastic)
• Expansion tanks (bladders)
• Holding tanks
• Water hammer arrestors (pistons)
• Water softeners (brine tanks)
• Valves, backflow preventers, etc.
• Lubricants & other

Plumbing components water hammer arrestors surge tanks under sink filters

Bacterial Attachment to Selected Surfaces

Legionella pneumophila (highest

attachment to lowest) 1. Latex 2. Ethylene-propylene 3. Chlorinated polyvinyl chloride 4. Polypropylene 5. Mild steel 6. Stainless steel 7. Unplasticized polyvinyl chloride 8. Polyethylene 9. Glass

• Aeromonas hydrophila (highest

attachment to lowest)

1. Polybutylene 2. Stainless steel 3. Copper

Bacteria biofilms within the clinical setting: what healthcare professionals should know, D. Lindsay, A von Holy, Journal of Hospital Infection, 2006.

Design Practice

• Redundancy
• Dead-leg Piping
• Balancing return hot water
• Zoning for Maintenance
• Sizing Equipment to Handle Peak Loads
• Lack of actual data on hot water usage

When looking at design what do we need to be concerned about in the system? Expansion tanks Water hammer arrestors Dead end connections Amplification devices Flow restrictors Other locations of concern:

• Dialysis
• Lab water
• Cooling towers
• Ice machines

Riser plan risk? System Component Risk

Mitigating Legionella

• Chemical treatment – cost, corrosion
• Use heat to disinfect the pipes – risk

scalding

• Use technology, such as electronic copper-

silver ionization, to reduce bio-film

• Conduct regular cleaning and flushing of

entire piping systems – when?

• Find disused fixtures and develop a flushing

protocol at those locations

• Better Fixture Design

Control-Waterborne

• Design – potable water; cooling towers
• Maintenance
• Temperature >140° F?
• Treatment of water

– Municipal source – In-hospital treatment

• Source recognition

– Water reservoirs – Dead-legs & dormant

• Flushing pre-occupancy

Alert Organisms from Clinical Microbiology Rounds

• Water bacteria

– Pseudomonas aeruginosa – Burkholderia cepacia – Serratia marcescens – Acinetobacter calcoaceticus var. – Chryseobacterium meningosepticum – Aeromonas hydrophillia – Atypical Mycobacterium species

• M chelonae, M.avium, M.mucogenicum,
• M.gordonae, M.fortuitum, etc.

– Legionella species

• L.pneumophila, L.bozemanii, etc..

The bacteria are there but we notice them only when they become resistant. Some of these microbes have doubling times of around 20 minutes

Infection Control Risk Assessment for Water Systems

Risk Analysis of Critical Control Points

1) What at risk patients are treated in the hospital

• oncology, transplantation, advanced surgery

2) Environmental Critical Control Points

• water supply, hot water system, cooling towers

3) Design for Control of Water Bacteria

• piping material, water temperature, storage

4) Operational Issues

• water flow rate, timers for backwash or flushers

5) Unusual events

• drought, fires, water main leak

6) Water stagnation

• During new construction, after disasters

ASHRAE STD 188 Prevention of Legionellosis Status under public review

Types of Hospital Water Usage

Type Potable Micro Standards Exposure to potential infection Legionella issue Drinking YES YES Aerosol ingestion YES Laboratory NO YES False positive NO Dialysis NO YES Endotoxin reaction/infection NO Process/heating- cooling NO YES Heat transfer YES Fire suppression NO NO Inefficiency NO

Adapted from ASHE publication: HACCP Plan for Prevention

• f Legionellosis Associated with Building Water Systems

ASHE Advocacy February 23, 2012

UMMC Water Usage 1999-2011

[Random Samples]

20000 40000 60000 80000 100000 120000 140000 160000 180000 1999 2001 2003 2005 2007 2009 2011 Water Usage (gallons per day)

Know the sources of water for hospitals CITY WATER SOURCE WELL WATER UMMC uses about 80,000 gallons a day Of city water UMMC uses about 2000 gallons a day for dialysis, cart washing and lab water.

500 1000 1500 2000 2500 3000 3500 4000 4500 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63

Incoming Water

East Building South Building

Start July 13, 2012 to October 8, 2013 7 day incubation on R2A Heterotrophic Plate Count South Building Average = 191 range 1 - 2610 East Building 747 4 - 4300

WATER DISTIBUTION SYSTEM BUILDING ISSUES RELATED TO DEAD END CONNECTIONS FROM DISCONTINUED LINES. Biofilm buildup from stagnant water and additives.

Why did the water usage go down?

• Switch to digital from chemical x-ray processors for Radiology
• Switch to air cooled from water cooled medical air compressors
• Lower gallons per flush
• Flow restrictors for faucets
• Automatic faucets for hand washing
• Waterless antisepsis for surgical and patient care hand cleansing

• Drinking water
• Kidney dialysis
• Laboratory
• Therapeutic
• Cooling
• Fire management

Water Systems in Healthcare

WATER SOURCES ARE VARIED IF YOU KNOW WHERE TO LOOK

Hospital Sources of Nonfermentative Gram-Negative Bacilli

Tap Water Humidification Water Distilled Water Sterile water

• r Saline

Nonsterile Water Faucet aerator Sink or wash basin Ice machine Water fountain Dialysis machine Pseudomonas aeruginosa

√ √ √ √ √ √ √ √ √

Pseudomonas fluorescens

√ √ √

Stenotrophomonas maltophilia

√ √ √

Acinetobacter species

√ √ √ √ √ √

Sphingomonas paucimobilis

√ √

Burkholderia cepacia

√ √ √ √

Ralstonia pickettii

√ √

Pseudomonas stutzeri

√

Adapted From: Chapter 34 - Non Fermenting Gram Negative Bacilli

• J. Flaherty et.al.

Hospital Epidemiology & Infection Control, Lippincott Williams & Wilkins 2004

Cluster Mycobacterium mucogenicum infections from water epi curve

Mpls water chloramine

What to do about water in a clinical setting?

Number of Samples Mean (CFUs/ml) Median (CFUs/ml) Range (CFUs/ml) Before Flush 16 49,471 25,050 110-196,000 After Flush 16 146 35 3-970

Automatic Faucets

Component parts harbor bacteria Instant water no adjustment first drop water Was the intention

• f AF to be:
• hands free
• water usage

Manual faucet

All soft rubber or cellulose components harbor bacteria Manual faucets require adjustment hence flushing fewer sources 1 type 2nd type

Breaking the chain of infection requires understand mode of transmission and reservoirs of the organisms.

In a suspect infection associated with water bacteria

• determine culture site
• sputum culture may indicate water usage
• ice for mouth care
• drinking water
• carafe or bottle
• source of drinking water
• wound infection
• water sources
• ice machines
• showers
• blood stream infection
• showers
• bathing methods
• procedures
• hand transmission potential
• water connectors
• hand wash sinks ??

Advantages Disadvantages Spread Plate

easy not sensitive to low levels low tech uses low volumes of water good screen

Broth

easy grows dominant bacteria low tech sensitive to low volumes

Membrane Filter

sensitive to low conc. higher tech specialized methods expensive

Methods to culture bacteria in water

Media for growth needs to have nutrients to repair damaged bacteria. R2A is considered the growth media for water samples but selective media can be used.

Ice machine maintenance

• charcoal filters?
• moldy storage bins

Ice maker

• sanitize surfaces
• internal parts

Drinking water standards: <1 cfu/100ml coliform bacteria <500 cfu/ml heterotrophic plate count Goal: prevent biofilm buildup Issue: stagnant water During construction water stagnates UMMC reduced water from 56M to 25M gal/yr over 13 years Are the water bacteria resistant?

Cardioplegia machine Dialysis water treatment Ultrasonic cleaner Water hammer arrestor

Will we be know what to when it happens?

Water Main Break Minneapolis 2013

Water Main Break Area Affected

January 2013

End Uses of Water in Hospitals

35% 15% 9% 7% 7% 7% 20% Kitchen/Dishwashing Landscaping Cooling and Heating Domestic/Restroom Medical Equipment Laundry Other

Water interruption planning

• Area
• Significant water uses
• Criticality
• Impacts if not resolved
• Alternatives/notes
• Contacts
• Phone numbers

Emergency Water Capture

Residents in Bermuda do not have fresh water source except what comes from the

• weather. Houses and buildings including the hospital collect water from the roof

for drinking water. Untold consequences can include contamination from bird droppings to cause fungal problems especially in visitors.

Basic Types of Disinfection Systems

1. Focal disinfection

– real time, no residual – UV, Ozone, instantaneous – not effective against previously Legionella contaminated system – works best in virgin waters

2. Systemic disinfection

– residual disinfectant: bacteriostatic or bacteriocidal – hyperchlorination, copper/silver, chlorine dioxide – super heat/flush: systemic but cannot be applied continuously

Data Analysis for Risk

• Percent outlets (+) legionella < 30%
• Number of organisms in water (concentration)
• Patient risk major factor
• The greatest risk lies with the patient being

Immune compromised and in a at risk building.

Drinking Water System Disinfection

• Superheat & Flush

– 158F (70C)

• Hyperchlorination

– Continuous 2-6ppm free chlorine residual – Bolus intermittant 17ppm

• Instantaneous Steam Heating

– Flash heating 88C – Blend water & recirculate

• Ultraviolet Light

– No residual – Maintenance essential

• Ozone

– Effective microbiocide – No residual

• Metal ion

– Silver & copper – Electrostatic stresses affect cell death

• Continuous chlorination

– Chlorine dioxide

Options for Disinfection of Drinking Water Systems

PH Biofilm penetration Residual EH&S Aesthetic quality Pro/Con Copper / Silver

(continuous)

8 Yes depends

• n PPM

Yes toxic None pH affect Chlorine dioxide 10 Yes Yes No THMs Taste &

• dor

Residual testing Hyperchlorination 7.8 minimal No THMs taste &

• dor

flushing Super heat / Flush NA Yes No None NA Labor Scalding Monochloramine 8-9 minimal Yes <THMs Taste &

• dor

Effective Difficult UV light NA No No None NA No residual Point of Use filtration NA NA No None NA easy

Chlorine dioxide is a stable water disinfectant that can be added to an existing water distribution system. The methods of adding chemical to the water supply makes the hospital a secondary water treatment facility needing added sampling for residual and by product.

Electrochemical Activation of Water

While spigots may get contaminated the removal

• f the microbial load prevent

colonization and/or infection. Point of use filters are not a long term solution but a short term to allow time for correction. Silting index of water determines plugging time till exchange.

Microbial Control with Chlorination

• In 1990 - 23% of municipalities in US with >50,000 people used mono

chloramine disinfection

• Advantages:

– does not form trihalomethanes – heat stable – more effective at penetrating bio film Hospitals with outbreaks of Legionellosis predominately >200 beds

• 73% of those hospitals have a transplant program
• 31 outbreaks in hospitals with free available chlorine
• only one outbreak with mono chloramine
• Chlorine dioxide

local production for legionella management (PCU area or whole hospital?) long term disinfection Royal Infirmary Glasgow Scotland (10 years)

• Electro chemical activation of water and brine to produce disinfection products

Impact of Monochloramine on Legionella colonization

Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 12, No. 4, April 2006 Two year prospective study in San Francisco when monochloramine replaced chlorine for municipal water disinfection.

• Building Legionella colonization decreased from 60% to 4% in 53

buildings studied.

• Point of use outlets were tested in those buildings.

Chlorine results of 617 outlets 39% were colonized while 1% of the outlets were colonized after chloramine disinfection initiated.

Gulick diagram

68

Chlorine testing in Water Microbiology of Water Advantages:

• Easy
• Relative inexpensive
• Real time

Advantages:

• More definitive

Disadvantage:

• Not definitive

Disadvantages:

• Delayed results
• Expensive
• Complex

What to do with water?

• Does the hospital treat severally immune

compromise patients?

• Is there an incidence of waterborne isolates?

If yes for the 2nd then it may be too late. Should we plan for if risk is there? or Should we plan because the bacteria are there? Resistance is what triggers concern! Water bacteria are common.

Stagnant water will allow for amplification & attachment to for biofilm. What can be done?

• Move water. During construction or low census water inactivity will

allow for bacteria growth.

• Use anti bacterial products like copper pipe. Be careful of plastic pipe

water bacteria like to attach.

• Do not store pipes outdoors where dirt can accumulate as well as vermin

may set up housing.

• Flush pipes after filling with water.
• Know the patients at risk and emphasize that mitigation in those areas.

Risk Analysis

• Patients spectrum of risk
• Transplant patient mouth care should they include tap water ice?
• Source water for drinking and ice
• If water sampling is suggested consider

longer incubation for true test of bacteria in water (7 day) incubation time should match patient isolate retention time

Criteria to determine if microbes in water pose a health risk?

• Clinical history of a water bacteria causing disease after exposure.
• Epidemiological evidence that DW is the major source of disease.
• The causal infectious agent is present in water.
• There is evidence that the ID agent is not readily removed by

normal water treatment

• There is evidence it survived treatment and is viable.
• There are robust analytical methods for identifying the agent.
• The analytical methods are certified by public health agency.
• There is evidence the implicated bacteria are in sufficient numbers

to cause problems.

University of Minnesota Medical Center-1986 UMMC Amplatz Children’s Hospital-2011

Questions and Answers

strei001@umn.edu