Legionella risks from spa pools, hot tubs, leisure and ...
Transcript of Legionella risks from spa pools, hot tubs, leisure and ...
Legionella risks from spa pools, hot tubs, leisure and health
centres.
26/04/10 LEEgionella LTD. Putting the LEE into Legionella Control 1
Dr Susanne Lee (formerly Surman-Lee) Leegionella Ltd Email:- [email protected] www.leegionella.co.uk Tel. +441895 674141 Mobile +447970018703 Registered Office 5 Ribblesdale Place, Preston, Lancs.
Spa pool definition (may also be called :- Whirlpools, Whirlpool baths, Whirlpool spas, Bubble pools, Hot tubs, Heated spas, Jacuzzis™)
• ‘self-contained body of warm water designed for sitting rather than swimming in, and has a mechanism to ensure the water flows around the user’
• Water usually kept between 30°C and 40°C
• Present in health clubs, health spas, hotels, sports centres, beauty shops/ centres also domestic premises
∗ 33 cases 6 deaths over several months Nov 2011 to June 2012 ∗ linked to a hotel in Calpe, Alicante, Spain
∗ Hotel closed 3rd July, source spa pool positive, airflow experiments showed that the aerosols from the pool could escape from the copula in reception
∗ Pool and associated pipework removed
http://www.ecdc.europa.eu/en/publications/Publications/060712-RRA-outbreak-Legionnaires-disease.pdf
Diamante Beach Hotel, Calpe, Spain
Mixed outbreak of legionnaires' disease and Pontiac fever associated with spa pool ( CDR 14 September 2006 )
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∗ 2 confirmed cases of legionnaires’ disease, three confirmed cases of Pontiac fever and a further 73 probable cases of Pontiac fever
∗ Flu-like symptoms including fever, myalgia, headaches and nausea over the previous week.
∗ Incubation period 24 and 48 hours, with symptoms lasting three to five days.
∗ Investigations revealed that all reported cases had been in the spa pool (or in very close proximity to it) over a period of at least seven days.
∗ There were no reports of illness in members who had used other facilities in the club.
∗ Water samples from the spa pool, the return flow from the massage jets and a short section of segmented pipe connected to mains water used to top-up the pool have all tested positive for Legionella pneumophila serogroup 1.
∗ .
∗ Figure Onset date and time for confirmed and probable cases (n=78) (one case onset unknown, one case 21/8/06, and one case 26/8/06)
You don’t have to be in a spa pool to get legionnaires’ disease
∗ Horticultural show, Netherlands Feb. 1999. ∗ Overall 242 cases with 28 deaths ∗ 77,061 visitors.
∗ Risk of infection increased with time spent near spa ∗ 2 spa pools on display positive for patient type ∗ 1 misting machine positive for other type
∗ Trade fair in Kapellen, Belgium, 1999 ∗ 80 persons who developed clinical symptoms, 13 had
positive urinary tests 4 deaths. ∗ Over 60.000 visitors attended the fair,
∗ Hot tub on display in Warehouse, Stoke on Trent ∗ July 2012 ∗ 2 deaths 19 other cases ∗ Distinct type in patients and pool ST 1268
Spa pools- potential source of infections if not designed; managed or maintained ∗ Spa pool features
• Not drained, cleaned or refilled between each use
• Water recirculated with filtration and (hopefully) chemical treatment
• Fitted with water and / or air jet systems
• Different designs for Commercial or Domestic premises
Commercial –overflow type suitable for commercial use
∗ Under most UK & European standards, an overflow spa pool is required for medium to heavy bathing loads.
∗ Overflow (deck-level) spa pools maintain the water level at a constant height with the excess water overflowing into a balance tank then replaced when bathers get out
∗ The water overflows into the channel creating an effective surface skimming action and then returns to the balance tank by gravity.
∗ The filtration system of a commercial overflow spa pool takes its water from the balance tank, which will automatically be topped up to a level of about 250mm.
Risk Assessment Review pool operation ∗Events in immediate past? ∗Microbiological samples ∗Chlorine / disinfectant measurements ∗Filter operation and design
∗air scouring, inspection windows,sizing relative to pool size, turnover, frequency and procedure of back-washing, last sand replacement
∗Leaking sewers, cross connections etc.
Spa pool risk factors
∗ Quality of source water
∗ Is it filled with a with a hosepipe?
∗ Poor design
∗ Poor training
∗ Lack of maintenance
∗ Lack of recovery period
∗ Poor control of pH and biocide levels
∗ Choice of biocide is it treated with Bromine or chlorine
Exacerbating factors
∗Nutrients from bathers e.g. dead skin, sweat and other body secretions, bath oils, body lotions soaps, urine faecal matter etc.
∗elevated temperature encourages growth of bacteria including pseudomonas and legionellae
∗Air and water circulation systems provide a large surface area for biofilm development
∗biofilm organisms x1000 times more resistant
A single modern spa pool may contain as much as 75 metres of flexible and fixed pipes with a total surface area of 550m2
Design issues-poor pool design ∗ Eg Balance tank not accessible
∗ Pipe work not removable for cleaning and draining
∗ Not suitable for commercial premises
∗ Inappropriate site
Maintenance issues ∗ Infrequent backwashing
/ water replacement
∗ Lack of cleaning / disinfection
∗ Replacement of old / corroded / scaled equipment
∗ Removal of redundant pipework – areas of stagnation
UK Survey of spa pools in hotels / leisure clubs showed :
– No risk assessment – Poor design - Balance tanks inaccessible for adequate cleaning – Domestic tubs in commercial premises – No or inadequate levels of biocide detected – Poor training – Unfamiliar with pool system – Unaware of health and safety duties /legislation – Failures of equipment – Fraud – Make- up water bypassing treatment – Inappropriate sampling points – Failure to act on adverse results
Training issues ∗ Transient staff
especially in hotels ∗ Lack of: ∗ Knowledge of Health
and Safety Legislation ∗ Understanding of pool
systems ∗ Understanding
importance of disinfection regime
∗ Appropriate poolside monitoring
Those pools with no appropriately trained staff are more likely to fail at least one of the microbiological tests
Number of trained staff
Disinfection problems
∗ No / infrequent monitoring of disinfection
∗ Poor pH control ∗ Lack of recovery period ∗ No calibration of measurement
probes ∗ No appropriate action on
adverse results ∗ No action on breakdown of
dosing equipment ∗ Choice of disinfectant bromine
treated pools more likely to have adverse results
Hot Tubs Conventional (rim) types - water level 150mm to 200mm below the top to accommodate bathers. Suitable for domestic use only
Hot tubs have caused outbreaks of: •Legionnaires’ disease
•Pseudomonas folliculitis
•Mycobacterium avium / fortuitum infection
Hot tubs- growing domestic market ∗ Approx 15000 installed in UK private homes last
year ∗ Increased potential for outbreaks as more installed
in commercial settings ∗ In the UK there is a requirement by the Trade
association for handover and training ∗ but still poor understanding of for example • Risks associated with poor treatment regime • Biocide treatment • Water turnover / replacement • Cartridge cleaning • Poolside testing
Legionella has been isolated from whirlpool baths
∗ Legionnaires disease has not yet been linked to whirlpool baths – but only sporadic cases from these sources would be likely Domestic owners must make sure they are cleaned an disinfected regularly, preferably after each use Designers should minimise pipes, make the pipes easily detachable for cleaning and make sure there is no moisture left in pipes after use
Growth of waterborne pathogens can occur in pools & associated system components and also in the pool environment
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Putting the Lee into Legionella Control 40
Within leisure complexes: many uses of water and many potential sources of infection including:-
∗ Pool area ∗ Swimming pool ∗ Learner / children's pools ∗ Spa pool ∗ Inflatables ∗ Toys / play equipment ∗ Interactive water features/sprays ∗ Wave pools
∗ Health spa ∗ Hairdressing salon ∗ Whirlpool baths ∗ Foot spas ∗ Showers/ experience showers ∗ Saunas ∗ Steam rooms etc.
∗ Buildings services ∗ Cooling towers/evaporative
coolers/humidifiers etc.
∗ Hot and cold water systems
∗ Drinking water
∗ Water for food preparation
∗ Water dispensers
∗ Food display humidifiers
∗ Cleaning equipment
∗ Decorative fountains
∗ Rain water collection
∗ Recycled / grey water use
∗ Temporary buildings
∗ Jet washers
∗ for leisure complexes assessors should have expertise in: ∗ public health aspects of water quality; ∗ legislative requirements, standards and codes of practice; ∗ the development of WSPs; ∗ all water systems including pool systems, other water-using devices and
equipment; ∗ identification of hazards and potential sources of these hazards; ∗ the type and nature of hazardous events ∗ the determination of risk; ∗ identification and assessment of appropriate control measures; ∗ operational monitoring procedures to ensure that the control measures
remain effective; ∗ verification and audit procedures.
. Risk assessors need the expertise, knowledge & resources to undertake the task competently
The existing controls should be reviewed to assess if they are effective at reducing the risk of infection
– Are the control measures effective – Temperature, biocides, pH etc. • Are users encouraged to shower before use of pool – – Washing with soap and water; especially young children – Design so flow of users through showers before pool – Drainage of showers to waste not into the pool – Children who are still incontinent should use waterproof bathing costumes • Are users educated – If had diarrhoea in preceding 14 days they should not use the pool – Not to swallow water – Wash hands after using toilet; nappy changing (have separate nappy changing area
readily accessible). – Encouraging children to use toilet • Is the risk of contamination limited from outside sources e.g. – Wearing of overshoes around the pool – Not allowing prams etc on the poolside
Validation and verification of WSP
∗ Validation -to ensure the WSP effective in each system under routine and adverse conditions
∗ Verification-Developing verification protocols to show your system remains under control ensuring the system remains effective to determine if health based targets met
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∗ Should follow similar general principles as applied to Drinking-water supplies ∗ Authorities responsible for regulation of recreational facilities should ensure the
implementation of safety plans, ∗ WSPs should address pools and hot tubs; also other water systems, including
cooling towers/ evaporative condensers ∗ The dose response is not easily described, therefore control measures should be
defined in terms of practices that have been shown to be effective:- ∗ including appropriate design, ∗ minimizing the available surface area within the pool and hot tub system and
associated pipework to reduce the area for possible bacterial colonization, ∗ ensuring an adequate disinfection residual in pools and hot tubs, ∗ proper maintenance and cleaning of equipment, and adequate ventilation.
In conclusion Water safety plans in leisure facilities:- WHO position