Legionellosis Water Management and Investigation Case Study

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1 Legionellosis Water Management and Investigation Case Study Michigan Department of Health and Human Services Bryce Spiker, MPH Legionellosis Epidemiologist Mike Wesenberg Environmental Health Specialist

2 Agenda Legionellosis overview and surveillance Public health investigations Situations that warrant investigation Environmental assessments and sampling Long-term care case study

3 Clinical Description Legionellosis is associated with two clinically and epidemiologically distinct illnesses: Legionnaires Disease Fever, myalgia, cough, and clinical or radiographic pneumonia May also see: headache, chills, shortness of breath, GI symptoms, and confusion Pontiac Fever Primarily fever and muscle aches (flu-like)

4 Clinical Description Cont. Legionnaires Disease Clinical Features Pneumonia Flu-like illness Hospitalization Common Uncommon Treatment Antibiotics None Case Fatality Rate 9-25% 0% Attack Rate <5% >85% Incubation Period 2-10 days (typically 5-6 days) 1-3 days Isolation of Organism Possible Never Pontiac Fever Pathogenesis Replication of Organism Inflammatory response to endotoxin

5 Causative Agent: Legionella Gram-negative bacillus Primarily found in freshwater Intracellular parasite of free-living protozoa Can live and grow in biofilm More than 60 species L. pneumophila: ~80-90% of reported US cases

6 Transmission Inhalation of contamination water droplets Aspiration of drinking water aka wrong pipe Soil (rare) NOT person to person

7 People at Increased Risk Not everyone exposed to Legionella becomes sick. People are more likely to develop LD if: Smoker (current or former). Smoking damages the lungs, making people more susceptible to all types of lung infections Have a weakened immune system as a result of HIV/AIDS or certain medications (corticosteroids or drugs for organ transplantation) Have a chronic lung disease such as COPD or another serious condition such as diabetes, kidney disease or cancer Are 50 years of age or older

8 From Fresh Water to Clinical Disease

Incidence (cases/100,000 population) 2000 2002 2004 2006 2008 2010 2012 2014 2016 Legionellosis Incidence

9 Incidence (cases/100,000 population) Legionellosis Incidence Trends National Trends Michigan Trends Legionnaires Disease in Michigan Year

10 Increases are apparent across the country, even with geographic differences in incidence 2005 Rates of reported legionellosis cases by state, 2005 Cases/100,000 population

11 Increases are apparent across the country, even with geographic differences in incidence 2010 Rates of reported legionellosis cases by state, 2010 Cases/100,000 population

12 Increases are apparent across the country, even with geographic differences in incidence 2015 Rates of reported legionellosis cases by state, 2015 Cases/100,000 population

medications More people living longer with

13 Possible Reasons for Increase in Cases Increased susceptibility of the population Aging U.S. population More people on immune suppressing medications More people living longer with chronic illnesses More Legionella in the environment Warmer temperatures Aging infrastructure Water-saving building modifications Improved diagnostic capabilities/improved diagnosis and reporting

14 Where Can Legionella Grow and/or Spread? Legionella can grow in: Hot and cold water storage tanks (growth) Water heaters (growth) Water-hammer arrestors (growth) Expansion tanks (growth) Water filters (grow) Aerators (grow & spread) Faucet flow restrictors (grow) Pipes, valves, and fittings (grow)

spread) Centrally-installed misters, atomizers, air washers, and humidifiers (grow & spread) Ice Machines

15 Where Can Legionella Grow and/or Spread? Legionella can grow & spread in: Electronic and manual faucets (grow & spread) Medical Devices (grow & spread) Centrally-installed misters, atomizers, air washers, and humidifiers (grow & spread) Ice Machines (grow & spread) Eyewash stations (grow & spread) Hot Tubs (grow & spread) Decorative Fountains (grow & spread) Cooling Towers (grow & spread) Showerheads and hoses (grow & spread)

16 Water Management Program Resources

17 ASHRAE Standard Gold Standard Establish minimum risk management requirements for building water systems CDC Toolkit based on this Standard 7 step HAACP based program

18 Translates ASHRAE 188 for wider audiences Plain language Step-by-step guide to creating a water management program FREE on CDC website

19 ASHRAE Standard Information and guidance to limit Legionella in building water systems Environmental and Operational Guidelines Technically oriented document

policies to inhibit microbial growth in building

20 CMS Memorandum Released June 2017 Requires healthcare facilities to develop and adhere to policies to inhibit microbial growth in building water systems (water management programs) Effectively Immediately

21 CMS Memorandum Update Updated July 2018 Clarified expectations for providers Conduct facility risk assessment, develop and implement WMP, specifies testing protocols and acceptable ranges for control measures, etc.

Elements of a Water Management Program Program Review Programs should be reviewed yearly and when the following events occur: Data review shows control measures are persistently outside of

22 Elements of a Water Management Program Program Review Programs should be reviewed yearly and when the following events occur: Data review shows control measures are persistently outside of control limits A major maintenance or water service changes occurs One or more cases of disease are thought to be associated with your system Changes occur in laws, regulations, standards, or guidelines

23 Outbreak Investigations

24 Investigation Steps 1. Collect Epi Data Legionellosis is national notifiable disease 2. Determine if Investigation is Warranted 3. Pre-Assessment Actions 4. Environmental Assessment 5. Sampling Strategy 6. Remediation (if needed) 7. Follow-up

25 2. Is an Investigation Warranted? 1 definite healthcare-associated case 2 possible healthcare-associated cases 2 common exposures Hot tub, hotel, work site, etc. Treat cases that never left a location like a definite HCA case

26 Healthcare-associated Legionellosis Among patients who meet clinical and lab criteria for confirmed LD: Definite healthcare-associated: patient who spent entire 10 days before date of symptom onset in a healthcare facility Possible healthcare-associated: patient spent a portion of 10 days before date of symptom onset in a healthcare facility

27 3. Pre-Assessment Actions Case-by-case basis Definite HCA case Two common exposures Past examples: Close down showers (all showers or specific) Remove aerators from bathroom sink faucets Bottled water restrictions for individuals with swallowing difficulty Restrict use of ice machines Install 0.2 micron point-of-use filters Prospective active surveillance

28 4. Environmental Assessment Request attendance of Facility Engineering Copy of Water Management Program Maintenance logs and blueprints available for review Test Environmental Parameters with: ph & Chlorine test kits, thermometer

29 5. Sampling Strategy Coaches EH professionals towards possible sample sites Environmental Parameters testing equipment Bulk water and swab sampling supplies PPE (as needed)

30 Sampling and Environmental Parameter Supplies

31 6. Remediation Thermal ( F, minimum of 5 min. at each POU device) Hyper-Chlorination (>2 mg/l at each device, contact time >2hrs) Cooling Towers (dump water, physical cleaning, treat with oxidizing and non-oxidizing biocides) Hot Tubs (drain, clean, hyper-chlorinate or hyper-brominate, change filters, maintain proper oxidizing biocide residuals)

32 7. Follow-Up MDHHS BOL will test twice during a public health investigation First Sampling Post-remediation Sampling All other sampling to be completed by private contractor Establish Sampling Plan Request future sampling results

33 Case Study November 2017 Legionnaires Disease at Long-Term Care Facility

34 Case Timeline 10/23/17: Patient admitted to hospital with fever, increasing weakness, and cough 10/26/17: Diagnosed with Legionnaires disease 10/27/17: Case referred through Michigan Disease Surveillance System 10/27/17: Confirmed case never left facility Symptom onset 10/20/17 (Incubation period: 10/10-10/19)

35 Pre-Environmental Assessment 1) Documents and personnel Current status of facility water management plan Cooling tower water treatment logs for the last 3 months A list of construction activities over the last 3 months 2) Additional surveillance Information related to residents with a diagnosis of pneumonia retrospectively to August 1, 2017, including residents who currently being treated for pneumonia If residents have had pneumonia in the past month, perform urine antigen testing to determine if they have been exposed to the bacteria Initiate prospective active surveillance of all pneumonia cases in the facility to include concurrent collection of urine for antigen testing and sputum for culture

36 Pre-Environmental Assessment 3) Water Restrictions Closed down shower the case-patient used daily Installed POU 0.2 micron filters on all showers and sinks in bathrooms prior to remediation Removed faucet aerators from all sinks Bottled water restrictions for residents with swallowing difficulties

37 Found potable hot water systems operating at <120 F Environmental Assessment Highlights Facility had three hot water generating tanks No Water Management Plan in place. Construction Activities ongoing

38 LTC Facility Characteristics >100 beds Two stories with Basement Constructed in stages beginning in 1960s Average daily Census = 180 New Construction underway Cooling towers out of service for season

42 Remediation and Results Thermal remediation Multiple times Installed Thermostatic Mixing Valves at point of use devices Allows water system temperatures to be safely elevated to 140 F Environmental samples negative for Legionella after 2 months Drinking water restrictions removed Completed Water Management Program

43 QUESTIONS?

44 References ASHRAE 188: Legionellosis: Risk Management for Building Water Systems. June 26, ASHRAE: Atlanta CDC Developing a Water Management Program to Reduce Legionella Growth and Spread in Buildings. June, 5, Available from CDC Legionella - Homepage. March 16, Garrison LE et al. MMWR. 2016;65(22): Fields BS et al. Clin Microbiol Rev. 2001;15(3):506-26

National Legionnaires Disease Surveillance, Outbreak Detection, and Response

National Center for Immunization & Respiratory Diseases National Legionnaires Disease Surveillance, Outbreak Detection, and Response Ally Binder, MS Surveillance Epidemiologist Respiratory Diseases Branch