LEGIONELLA MANAGEMENT & CONTROL. IS IT WORTH WORRYING ABOUT?

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LEGIONELLA

MANAGEMENT & CONTROL

IS IT WORTH WORRYING ABOUT?

LEGIONELLOSIS

Legionella = water-borne bacteria Naturally widespread in the environment Over 50 different species identified 20 known to cause disease in man Legionella pneumophila

– Legionnaire’s Disease Pontiac Fever / Lochgoilhead Fever

LEGIONELLA

Temperature range 20 - 50°C Proliferates at 37 °C Requires nutrients Slow moving / stagnant water Poorly managed water system

= perfect environment

INCIDENCE RATES

300+ cases/year - England & Wales Steady rise in cases since 2002 Studies show LP could be responsible for 2-

3% of community acquired pneumonia (approx 83,000 cases of CAP) so 2,500?

Treatment is cheaper than testing 10-12% mortality rate Respiratory disease

CASES BY YEARTotal Number of Cases in UK

0

100

200

300

400

500

600

Year

Nu

mb

er

of

Ca

se

s o

f L

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Barrow Outbreak

‘AT RISK’ GROUPS

0

50

100

150

200

250

Cases

0-9 10-19 20-29 30-39 40-49 50-59 60-69 70+

Age in Years

England & Wales Cases

MaleFemale

EU SURVEILLANCE

ENVIRONMENTAL FACTORS

WHERE IS IT ACQUIRED?

Distribution of Where Legionnaires' Disease was Acquired 1980-2006

Nosocomial

Travel Outside UK

Travel Within UK

Community Aquired

CHAIN OF EVENTSBacteria present in water system

Slow moving / stagnant water

Adequate food source

Temperature range 20-50°C

Aerosol formed

People present

OUTBREAKS

SHOWERS

Operate at ideal temps

Poor hygiene

Infrequently used

Prone to scaling

Create aerosol

DEAD LEGSStagnant water

Ambient temps

Breeding ground

STORAGE TANKS

Over capacity

Stagnation

Out of sight

Poor flow

Ambient temps

CALORIFIERSCan run at critical temps

Thermal stratification

Sludge build up

COOLING TOWERS

Run at ideal temps

Open to elements

Contamination via water supply

Intermittent use

Drift affects wide area

CASE HISTORY

Hospital outbreak - Glasgow 1992 1 patient died Source = fire hose ‘Deadleg’ Need for awareness

THE LAW

Health & Safety at Work Act (1974) COSHH Regulations (2002) Notification of Cooling Towers

Regulations (1992)

Approved Code of Practice (1992) Revised ACOP January 2001

RESPONSIBILITY - ACOP

Identify & assess sources of risk Prepare scheme to prevent/control the risk Implement & manage control programme Keep Records Appoint a responsible person

RESPONSIBLE PERSON

Managerially responsible for implementation & supervision

Ensure all those involved are trained and competent

Manage contractors and suppliers Maintain records Ensure regular reviews are carried out

CAUSES OF OUTBREAKS

KEY FACTORS

Poor communication (internally) Responsibilities not defined Lack of training Failure to record meetings / conversations Insufficient contract documentation Poor advice / management Risk assessment not carried out

2012 OUTBREAKS

Edinburgh – 101 cases, 3 deaths – North British Distillery Company – HSE Improvement Notice (failure to

devise & implement a sustained & effective biocide control programme in one cooling tower)

– Macfarlan Smith  – HSE Improvement Notices require thorough cleaning of one cooling tower & provision of access for inspection & maintenance.

– All three notices have been complied with, and the HSE has stressed that the notices do not mean that the cooling towers have been identified as the source of the outbreak

Stoke on Trent – 21 cases, 2 deaths– JTF discount warehouse in King Street, Fenton, where a hot tub on display

was singled out as the probable source of the bug

COST TO BUSINESS

Sick pay Loss of production / skills Cost of an investigation (FFI) Prosecution & Civil Action Bad publicity - loss of business Employee de-motivation

RISK MANAGEMENT

Risk assessment Regular monitoring Temperature control Water Treatment Maintenance & Cleaning Annual review Awareness

RISK ASSESSMENT

‘Suitable & Sufficient’ - all water systems Reviewed regularly (bi-annually) and where:

– change to plant / water system or its use– change to the use of the building– new information about risks / control measures– tests indicate control measure are ineffective

Carried out by competent person

BS8580

Establish a standard approach to working Encourage risk assessment rather than ‘surveys’ Meet standards expected by the HSE / EHOs More emphasis on

– Appraisal of records and control measures– Incidents of persistent non-compliance– Training and competence of site personnel– Timely completion of recommended remedial work

SCHEME FOR CONTROL

Weekly flushing - infrequent use services

Monthly temperature monitoring - sentinel taps & calorifiers

Quarterly shower head disinfection / de-scaling

6 monthly storage inspections

Annual review of scheme and risk level

Bi-annual review of the risk assessment document

Cleaning and disinfection as required

LEGIONELLA MONITORING

Programme for continual risk assessment Early identification of problem areas Demonstrate effective control Visual inspection – cleanliness / operation Compliance with current guidance

CONTRACT MANAGEMENT

Use registered suppliers – LCA BS 8580 / BS 8558 Check training records / CVs Ask for references Agree levels of service Agree areas of responsibility Review contract at quarterly intervals Check log book records regularly

FUTURE TRENDS

Rise in susceptible individuals Increased installation of TMVs

– (new building regs – required on all baths / showers) MRSA / Swine flu – increased use of alcohol

gel Office water coolers / boilers IR no touch taps (low flow areas) Increase in solar heating installations Global warming

IS IT WORTH WORRYING ABOUT?

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