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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
D
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?