Advanced management and control of a Legionella outbreak in a full service hospital – clinical and technical collaboration. Dr Vyt Garnys1, Paul Bartley2, Raghuram Muguli3

1 CETEC Pty Ltd, Melbourne, Australia 2 The Wesley Hospital, Brisbane, Australia 3 CETEC Pty Ltd, Sydney, Australia

WE WILL LOOK AT

• Limitations of published remedial

options

• Monitoring strategies

• Rectification strategies

• Case study

• Path to regulation

.

All cold, hot and warm water

designs have the potential to

house microbially active

matter due to their complex

design, fittings and intermittent

use

BIOFILM IN PLUMBING SYSTEM

.

DEWHA 2008

HEATED WATER DESIGN INITIALLY SIMPLE

.

POTABLE WATER DELIVERY NOW INCREASINGLY COMPLEX

.

EVEN ACCESS IS NOW INCREASINGLY DIFFICULT

AND DEPOSITION LOCATIONS MORE FREQUENT

.

• Dead Legs, Pipe walls, TMV’s,

Taps, Showers

• Washers, o-rings, ABS plastic,

flexible hoses

• Storages, cold and warm

systems

KEY BACTERIAL BREEDING POINTS

• Often neglected as a repository of biofilm

• Can be contaminated by earthworks, repairs and other

water supply quality issues and can seed cold and warm

water system either directly or through thermal mixing

values (TMV)

• Cold water pipes adjacent to warm water pipes,

refrigeration, ceilings and/or heating systems, ie. can be

warmed

• Active Legionella breeding is found in “cold” side of TMVs

• Need to disinfect both hot and cold water systems

• Need to maintain disinfection.

EVEN COLD WATER IS CONTAMINATED

.

THERMAL MIXING VALVE

Control Options (WHO)

Method Advantage Disadvantage

Periodic flushing with hot water at 50 – 60˚C

•Simple, Effective, easily monitored

•Not applicable to cold water systems •Requires protection against scalding •Must be maintained and inspected to achieve consistent control •Recolonization occurs within days

Chemical Options (WHO)

Method Advantage Disadvantage

Dosing with Sodium Hypochlorite

• Proven, effective disinfection technique • Simple to use • Relatively cheap

•Formation of trihalomethanes •Needs protection for dialysis patients •Toxic to fish •Affects taste and odour •Not stable, especially in hot water •Increases corrosion of copper

Dosing with monochloroamine

• More persistent than chlorine •Simple to use in mains distribution •Penetrates into Biofilm

•Needs protection for dialysis patients •Toxic to fish •Affects rubber components •Limited commercial kits available

Chemical Options - Cont (WHO)

Method Advantage Disadvantage

Dosing with Chlorine dioxide

• Proven disinfection technique • Simple to use

•Formation of chlorite

•Needs protection for dialysis patients

•Safety considerations (dependent on method of generation)

Ultraviolet disinfection •Proven disinfection technique •Simple to use

•Effective only at point of application (no residual)

•Not suitable for turbid waters

•No effect on Biofilm formation

CASE STUDY

TREATMENT HISTORY

• Several heat treatment cycles (70 Deg C) conducted internally for 2 weeks

• Presence of Legionella (2x 10 days) still confirmed following heating

• CETEC contracted to provide expert advice and resolve issue to allow hospital to RAPIDLY return to full operation

MANAGEMENT STRATEGY

• Daily meeting of all key sector managers

• Establish multidisciplinary expert panel

• Establish physical remediation task group

• Establish expert communications task group

• Regular staff assembly progress briefings

• Ambulance bypass and no new patients (20% occupancy)

• Maintain ICU and dialysis operations on bypass water

• Dry washing and bottled drinking water

• Train and use 50 underemployed nurses to assist in remediation (tap flushing and testing)

CHALLENGES

• Understanding plumbing networks & condition

• Backflow water prevention to isolate buildings

• Not cutting all water to the hospital whilst installing backflow equipment (e.g. Maintaining water supplies)

• Management of occupants and critical patients within facility during treatment

• In this case, each of 5 hospital buildings were vacated in rotation but critical facilities were operated during remediation.

WATER & CLINICAL MONITORING

• A baseline was established for both Legionella & HCC plate count

• Implemented rapid same day microbial enzyme analysis technique (Mycometer - Bactiquant Water)

• Patient management, diagnosis, treatment & reporting requirements occurred concurrently.

RAPID REMEDIATION PROGRAM

No single ‘silver bullet’ therefore Integrated program of biofilm remediation required consisting of:

• chemical cleaning & hyper disinfection of pipework

• Ongoing chlorine disinfection of potable water

• ongoing removal of dead legs

• Ongoing monitoring

• 1-2 days remediation treatment per building

BIOFILM and DEPOSIT CLEANING OF PIPEWORK - STEPS

.

CHEMICAL AND CHLORINE DOSING

.

REMOVAL OF BIOFILM WITH ALKALINE DETERGENT

. MAIN TANK

STORAGE AND

MAINTENANCE

DOSING POINT

Examples of results#

Pre Treatment (cfu/mL) Post Treatment (cfu/mL)**

Area *HCC Legionella (SG1)

HCC Legionella (TL & SG1)

1 36,000 100 <10 <10

2 13,000 <10 <10 <10

3 1,900 10 <10 <10

4 13,000 >30,000 <10 <10

# Approximately 3000 samples,

5 buildings, 560 beds

A range of Species identified periodically,

** >99% at <10cfu/ml

OUTCOMES

• New admissions were made to the hospital in 13 days, full operation in 29 days from 20% occupancy

• Where reoccurrences of Legionella occurred, these allowed detection of dead legs which were subsequently removed

• Following removal of dead legs, and >3 months later, no reoccurrence of Legionella or HCC

• Rapid Mycometer HCC testing allowed for on-site control of efficacy of the decontamination and post treatment

• Invited to join Technical advisory panel (TAP) formed by Queensland state government in June

• TAP released “Preliminary Guidelines for Managing Microbial Water Quality in Healthcare Facilities” on the 24th October 2013

• Guidelines incorporate CETEC decontamination method and WQRMP

www.health.qld.gov.au/legionnaires/

Released 24th October 2013

ACKNOWLEDGEMENTS

• Richard Royle and all of the magnificent Wesley Hospital and Uniting Care team

• All of the CETEC and Foray Laboratories Team

• Glen Pinna and the Biotech Labs Team

• The Nalco water treatment Team

• Alex Mofidi and the AECOM water engineering Team

• Nicolas Massey and the Queensland Health Team

• Reviewers and Queensland HHS regional staff

QUESTIONS?

Queries to:

Dr Vyt Garnys

vyt.garnys@cetec.com.au

+61 3 9544 9111

THANK YOU,