Download Legionella Control - Institution of Occupational Safety

Legionella Awareness
Phil Land H2O Chemicals Ltd
11 May 2011
Background
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American Legion Convention 1976
Philadelphia, Bell Vue Stratford Hotel
182 cases with 29 deaths
Discovered by Dr Joseph McDade
Bacteria common in water and soil
How legionella multiplies
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Favourable pH & temperature 20 – 45C
Ideal is 37C (human body)
Key nutrients are free iron & L cysteine
Biofilm protection
Stagnation provides time for
multiplication
Single Bacteria
Facts About
Legionnaires’ Disease
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Between 400-550 cases in the last
couple of years
Under reporting is believed to occur
Legionella Pneumophila accounts for
most cases
At least 50 other species are known
Legionnaires’ disease in residents of England
and Wales by category of exposure 19802009
Data from HPA
Infection and symptoms
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Inhalation of bacteria as an aerosol
Incubation period 2-10 days
Sometimes difficult to diagnose
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severe pneumonia: dry cough, diarrhoea,
vomiting, breathing difficulty, high fever, chills,
headache, some become confused or delirious
Fatality rate is about 12%
Can be treated effectively with antibiotics
Legionella
colonising Amoeba
Susceptibility of Individuals
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Increasing age
Gender
Smoking
Existing respiratory disease
Illness
Treatment (dialysis or
immunosuppressant drugs)
Types of System
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Cooling systems (if applicable)
Domestic water services
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Hot water systems
Cold water systems
Spa Baths
Other systems
Examples of contamination
Cold Water Storage Tanks
CWST internal contamination
Showers
Tower Packing
Before & After
Before & After
What can you do to control
legionella?
System of Control
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Comply with the relevant legislation
Follow the ACoP L8 ‘The control of legionella
bacetria in water systems’
Carry out Legionella Risk Assessments and
review existing ones at least every 2 years
Robust monitoring and cleaning programmes
Comprehensive, accurate and up to date
records
Any Questions?