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PROSPECTIVE

Author Whiley expounds the view that routine testing of potable water systems for Legionella should be abolished from all guidelines and an emphasis alternatively be placed on maintaining control measures. This view is in direct contrast to the views of  the authors(Samuel Collins and Jimmy Walker) detailed below:

According to Collins and Walker it has been well established that a priority in any potable water system must be to establish and monitor appropriate control regimes aimed at limiting both the potential for Legionella to grow and its dissemination. Further to this, risk assessing control strategies forms the basis for many standards worldwide, including the UK Health and Safety Executive Approved Code of Practice L8 and the US ANSI ASHRAE guidelines.

As the authors state, however an over reliance on routine sampling results (which we appreciate only represent a snapshot in time) can induce a false sense of security and  so too can an over reliance on control measures alone. To illustrate this point - for three potable water systems who were epidemiologically linked with separate clusters and cases of Legionnaires’ disease (LD), control measures (e.g., temperature, and flow) were within recommended parameters and monitored as per national guidelines. However, extensive Legionella colonisation was present in key areas, notably where hot and cold water was mixed, e.g., post-thermostatic mixing valves and showers (unpublished data). Colonisation and risk were only identified by epidemiological data, i.e., when cases of LD were reported.

Their view is that routine testing at these critical control points would have given an early warning and may have prevented these cases from occurring. The availability of planned routine sampling results can also prove very useful in public health investigations of LD, where the colonisation history of a system under investigation (i.e., epidemiologically linked to cases) can help focus investigations and pin-point sources more readily.

These authors also make reference to health-care facilities where reducing the exposure of vulnerable individuals is a key priority. For most UK hospitals, a zero-tolerance approach to Legionella is based on the assumption that there is no known safe level of Legionella and that remedial actions are therefore implemented at the detection of any concentration of Legionella [7]. Unlike current Centers for Disease Control and Prevention (CDC) recommendations [8], routine testing plays a crucial role in the water safety plan approach to managing these healthcare systems, proactively identifying risk and offering an additional layer of security to prevent even a single case of LD occurring.

This approach, combined with clinical surveillance, has been shown to be effective in identifying and reducing cases of nosocomial LD [9].

With the well acknowledged limitations of Legionella monitoring, is the safest approach a combination of a risk assessment, control measures (including meticulous monitoring), and routine water testing? 

LPC Inc agrees with the authors that routine testing should be implemented on a system-by-system basis, informed by the risk assessment to reduce inappropriate or meaningless testing and expenditure and take into account the history of the system, the control measures, the previous test results, the population at risk, etc. The absence and detection of low concentrations of Legionella by culture (or by other analytical methods) combined with verified control measures are the ultimate reassurances that the microbiological risk has been managed appropriately. After all, cases of LD do not tend to be linked to systems where Legionella has not been detected [9,11,12].

At LPC Inc clients are advised that they may include initial testing of the system in the beginning and testing for validation annually or bi annually depending on results and risk categorization. As time goes by the data analysis will provide solid evidence for the reduction in the frequency of testing until you reach a state where detailed continuous monitoring is sufficient.

CEO

LPC Inc, 2019

References

1. Kirschner A.K. Determination of viable Legionellae in engineered water systems: Do we find what we are looking for? Water Res. 2016;93:276–288. doi: 10.1016/j.watres.2016.02.016. [PMC free article] [PubMed] [CrossRef] [Google Scholar]

2. David S., Rusniok C., Mentasti M., Gomez-Valero L., Harris S.R., Lechat P., Lees J., Ginevra C., Glaser P., Ma L., et al. Multiple major disease-associated clones of Legionella pneumophila have emerged recently and independently. Genome Res. 2016;26:1555–1564. doi: 10.1101/gr.209536.116. [PMC free article] [PubMed] [CrossRef] [Google Scholar]

3. Health and Safety Executive . Legionnaires’ Disease—The Control of Legionella Bacteria in Water Systems. 4th ed. HSE Books; London, UK: 2013. [Google Scholar]

4. American Society of Heating Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 188-2015 Legionellosis: Risk Management for Building Water Systems. ASHRAE; Atlanta, GA, USA: 2015. [Google Scholar]

5. European Working Group for Legionella Infections (EWGLI) EWGLI Technical Guidelines for the Investigation, Control and Prevention of Travel Associated Legionnaires’ Disease. 2011. [(accessed on 16 January 2017)]. Available online: http://ecdc.europa.eu/en/healthtopics/legionnaires_disease/ELDSNet/Documents/EWGLI-Technical-Guidelines.pdf.

6. Decker B.K., Clancy C.J. Culture positivity and bacterial burden thresholds for Legionella in hospital water: Proceed with caution. Am. J. Infect. Control. 2016;44:730. doi: 10.1016/j.ajic.2015.11.038. [PubMed] [CrossRef] [Google Scholar]

7. Department of Health . Health Technical Memorandum 04-01: Safe Water in Healthcare Premises—Part B: Operational Management. Department of Health; London, UK: 2016. [Google Scholar]

8. Centers for Disease Control and Prevention Guidelines for preventing health-care associated penumonia, 2003. MMWR Morb. Mortal. Wkly. Rep. 2004;53 (RR-3):1–36. [Google Scholar]

9. Stout J.E., Muder R.R., Mietzner S., Wagener M.M., Perri M.B., DeRoos K., Goodrich D., Arnold W., Williamson T., Ruark O., et al. Role of environmental surveillance in determining the risk of hospital-acquired legionellosis: A national surveillance study with clinical correlations. Infect. Control Hosp. Epidemiol. 2007;28:818–824. doi: 10.1086/518754. [PubMed] [CrossRef] [Google Scholar]

10. Florentin A., Lizon J., Asensio E., Forin J., Rivier A. Water and surface microbiologic quality of point-of-use water filters: A comparative study. Am. J. Infect. Control. 2016;44:1061–1062. doi: 10.1016/j.ajic.2016.02.028. [PubMed] [CrossRef] [Google Scholar]

11. Kool J.L., Bergmire-Sweat D., Butler J.C., Brown E.W., Peabody D.J., Massi D.S., Carpenter J.C., Pruckler J.M., Benson R.F., Fields B.S. Hospital characteristics associated with colonization of water systems by Legionella and risk of nosocomial Legionnaires’ disease: A cohort study of 15 hospitals. Infect. Control Hosp. Epidemiol. 1999;20:798–805. doi: 10.1086/501587. [PubMed] [CrossRef] [Google Scholar]

12. Yu V.L. Resolving the controversy on environmental cultures for Legionella: A modest proposal. Infect. Control Hosp. Epidemiol. 1998;19:893–897. doi: 10.1086/647759. [PubMed] [CrossRef] [Google Scholar]

FACTS

• Legionellosis refers to two illnesses associated with the legionella bacterium. When the bacterium Legionella causes severe pneumonia, the disease is referred to as Legionnaires’ disease. Legionella can also cause a less severe influenza-like illness known as Pontiac Fever.
• Most of the  cases of legionellosis are the result of exposure to Legionella associated with building water systems.
• The presence alone of Legionella bacteria in building water systems is not sufficient to cause legionellosis. Other factors including environmental conditions, water temperatures, etc. and a means of transmitting the bacteria to people in the building via aerosol generation are necessary to cause a sporadic case, a cluster  or an outbreak of disease as a result of exposure.
• People can get Legionnaires’ disease or Pontiac fever when they breathe in small droplets of water (Aerosols) in the air that contain Legionella:
• The case fatality rate for legionnaires disease ranges from 5-30%
• Given the incidence of Legionellosis and its associated harm, personal injury claims and litigation are becoming more frequent.
• Reported settlements and jury awards range from $255,000 to $5.2 million. In addition to negative media attention, business interruption and reputation damage.
• Keeping Legionella out of water systems in buildings is key to preventing infection.
• Water management programs identify hazardous conditions and take steps to minimize the growth and transmission of Legionella and other waterborne pathogens in building water systems.
• The European Surveillance Network reports that I out of every 5 cases of Legionnaires disease is travel associated.

ARE YOU TAKING LEGIONNAIRES’DISEASE(LD) SERIOUSLY ENOUGH? Take the test

Did You Know?

The United Kingdom (UK) is Barbados’s and the region leading source market. Tour operators are liable under the UK Package Travel and Linked Travel Arrangement Regulations 2018 (The Regulations). Under Regulation 33, persons other than the principal offender can be liable for damage sustained by a traveler. In this case, the tour operator would be the principal offender and hotels qualify as other persons. To date some hotels in the region have been held liable for negligently exposing patrons to the organism.

Are You In Compliance With Existing Regulations?

Implementing a water management program  the right thing to do for the people who spend time in your building and is cost effective for your organization. Building operators that manage water systems demonstrate good corporate citizenship. 

Preventing Legionella also protects you against loss of business, brand damage and legal risk. In litigation pertaining to Legionnaires’ disease, several guidelines have been used as a basis for determining “Standard of Care”/Duty of Care – whether the building operator exercised reasonable care in preventing disease associated with their water system.

Can You Defend Your Policies Based on Expert Opinions?

As noted by legionella experts " An attorney’s case against your water management practices is only as strong as the opinion of a qualified expert. The same goes for your defense. It’s not enough to have just any water  management program it must be comprehensive" .

Do You Know Whether Your Liability Insurance Covers Legionella-Related Claims?

 Building operators should be able to rely on their insurance coverage to pay the settlement (or in rare instances, the jury verdict), attorney fees, expert fees and other expenses associated with a suit over Legionnaires’ disease. But in recent years, some insurance companies have attempted to deny coverage based on policy exclusions (e.g. for pollution or bacteria) – sometimes successfully, sometimes not.

Find out whether your liability policy will pay Legionella claims.

It Must Work!

Implementing your risk management program and documenting the procedures are crucial for legal risk, too. If duty of care is not exercised It makes an easy case for the plaintiff’s attorney.

How did you score? Since the test covers only the basics, passing requires a yes to all five questions. If you failed, don’t panic; just get started on changing any nos to yeses.