INVESTIGATION, REMEDIATION & CONTROL OF FACILITY ASSOCIATED LEGIONELLA

Transcription

1 INVESTIGATION, REMEDIATION & CONTROL OF FACILITY ASSOCIATED LEGIONELLA Eric Weren, MSIH, Research Scientist, Environmental & Occupational Health Assessment Program

2 LEGIONELLA ORGANISMS Legionella are ubiquitous in natural and artificial fresh water environments Grows best in temperatures, F Dormant under 68 F killed above 124 F Proliferates large plumbing systems, hot tubs, whirlpools, cooling towers & decorative fountains Legionella pneumonophila serogroup 1 causes majority of human illness

3 Seasonality Surface water warmed in summer Reservoirs used for recreation in summer Cooling tower often online late spring to early fall

4 LEGIONELLA AMPLIFICATION Water from supplier is not sterile Insufficient Chlorine Temperatures: optimum F Grow F Water stagnation Scale and sediment Symbiotic with amoeba, protozoa & algae Rubber, some plastics support growth

5 Temperature by System Type

6 Amoeba Engulfment

7 Biofilm Entrapment

8 Warmer Temp. Low Cl Protozoa Biofilms Pathogen Respiratory Aerosol Proliferation Exposure Risk Risk of Contracting of Legionnaires Contracting Disease Legionnaires Disease Aerosolization Droplet Size Distance Aspiration Susceptible Population Elderly Immunosuppressed Immunosuppressed Elderly Chronic Respiratory Disease

9 LEGIONELLOSIS Legionnaires' Disease Low attack rate: 5% High mortality: 5-30% Incubation: 2-14 days Fever: F Breathing difficulty Cough (dry, phlegm) Chills Chest pain Pneumonia Pontiac Fever High attack rate: 90% No mortality Incubation: 1-3 days Muscle aches Flu-like symptoms Self-limiting

10 WHO IS AT RISK FOR LEGIONELLOSIS? Older people (>50 years of age) Current or former smokers Chronic lung disease (COPD or emphysema) Weak immune system from diseases: cancer, diabetes, kidney failure, HIV/AIDS Suppressed immune system (transplant operation or chemotherapy)

11 CASE DEFINITIONS Confirmed Legionnaires Disease: Clinical: fever, myalgia, cough and clinical or radiographic pneumonia (Pontiac Fever- no pneumonia) Laboratory: By culture: isolation of any Legionella from respiratory, lung tissue, other sterile site By urinary antigen: detection of L. pneumophila serogroup 1 in urine By seroconversion: fourfold or greater rise in antibody titer to L. pneumophila serogroup 1

12 REPORTING OF CASES NJDOH Communicable Disease Reporting and Surveillance System (CDRSS) Local Health Dept performs investigation Information needed includes: Illness onset & Incubation period Activities during incubation Potential exposures

13 LOCAL HEALTH DEPARTMENT INVESTIGATION Interview case patient & heathcare provider Confirm case meets legionellosis case definition Symptoms & timing, Determine onset and incubation period travel history during incubation period Identify potential water exposures Enter data from interview and pertinent medical information into CDRSS.

14 LOCAL HEALTH DEPARTMENT INVESTIGATION (CONT) Long-term care, hospital & Assisted Living: 1 Case => Full Environmental Investigation report to NJDOH/CDS by telephone. Community: Investigate specific exposures & other local cases with same exposure/building, investigate travel. Complete CDC Legionellosis Case Report CDC enters into a database looks for common exposures.

15 INVESTIGATION If linked to building, NJDOH generates an Outbreak Number (E-number) LHD and NJDOH to set up conference call with facility Facility Administrators Director of Nursing Infection Preventionist Facility Manager and Maintenance Information gathered on initial conference call: Clinical information on the case (Showering, nebulizer, oxygen, aspiration risk?) Possible water exposures of the case Building information (age, size, # of water outlets)

16 IMMEDIATE ACTIONS FOR FACILITY Immediate preventive actions: shower filters, bottled water, removing faucet aerators On-going surveillance for clinical pneumonias Hire water consultant with Legionella experience Schedule a walkthrough No water treatments before initial sampling

17 BUILDING INVESTIGATION Schedule building walk-through Facility management Facility maintenance Consultant LHD and NJDOH Perform Water sampling for Legionella Discuss Remediation Plan & follow-up Develop Preventive Maintenance Plan

18 BUILDING INFORMATION Age, size & construction, room configurations Renovation History Plumbing system Design Condition Number & type of water outlets Preventive Maintenance Connection to fire sprinkler system Heating/Cooling System Occupancy rate

19 BUILDING ASSESSMENT: Water condition (Cl, Temp & ph) Whirlpool spas and hot tubs, tubs Decorative fountains Cooling towers and evaporative condensers Recent or ongoing construction/renovation Repair or construction of public water system AC drip pan drainage (??)

20 SOURCES OF EXPOSURE Breathing mist Showers & aerators Nebulizers/Oxygen Humidifiers Hot tub/whirlpool Decorative fountain Cooling tower mist

21 SOURCES OF EXPOSURE Aspiration of water Ice machines Drinking tap water Eating food made with tap water

22 o Potable Water Systems

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24 PLUMBING SYSTEM RISK FACTORS Tanks sediment & temp stratification Biofilm & scale in plumbing Deadlegs stagnant water Pipes inappropriately capped off Underutilized plumbing (sections closed off, rooms unoccupied) Rubber gaskets & expansion tank lining Water temperature & low Cl levels

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27 Deadlegs

28 Operational Deadlegs

29 DeadLegs Emergency Safety Showers Janitor Sink Eye Wash Emergency Safety Laundry Tubs

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31 Ice Machines

32 Ice Machines Best Practices Follow Manufacturers cleaning and disinfection procedures. Use sediment (1-10 micron) and bacteria filters (0.2 micron). Follow manufacturers recommendation. Do not use carbon filters on ice machines unless required for odor/taste Use sterile water to clean and disinfect components. Use sterile or basin for soaking components. Avoid contamination of ice machine drains & trays.

33 PRE-REMEDIATION SAMPLING Use a CDC certified ELITE Laboratory ( Sample & process 1 liter Approximately 10% of outlets Rooms associated with case Rooms distal to the case room Unused & underused outlets All tank(s) top & bottom Hot water return(s) Incoming water (pre remediation only)

34 ENVIRONMENTAL SAMPLING Bulk Water 1 liter sterile nalgene bottle First Draw Measure Temperature Residual Cl Cooling tower

35 ENVIRONMENTAL SAMPLING Swab Shower heads & aerators Condensate drain pans Cooling tower components

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37 LABORATORY ANALYSIS Culture 14 days Most species & serotypes identified PCR (Polymerase chain reaction) Rapid turnaround (2 hours) Genetic test on DNA Species specific Viable & non-viable bacteria

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40 PRE-REMEDIATION ACTIONS Identify and remove dead legs Drain, clean, and flush water heater Remove and disinfect faucet aerators & shower heads Eliminate/minimize rubber, plastic, and silicone washers and gaskets Eliminate (flush) other points of stagnation Inspect sprinkler backflow preventers Biocides Protozoa, amoeba & biofilm protects

41 REMEDIATION-SHOCK TREATMENTS Superheat Post warnings Hot H 2 O tank drain & flush Raise temp to >160 F hold 3 hrs. Flush outlets >140 2 min hold 2 hrs. Check Temp every 30 min Reduce temp Hyperchlorinate Post warnings Isolate H 2 O tank drain & flush Raise Cl 2 to >50 ppm hold 3 hrs. circulate & test: 30 ppm Flush outlets draw & test: 30 ppm hold 16 hrs. draw & test: 10 ppm Reduce Cl 2 < 2 ppm

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44 Remediation Issues Time intensive for staff. Only a temporary solution: Bacteria in biofilms are not completely removed Rapid bacteria re-growth is common Must be performed 2-4 times/year (CDC) Outlets cannot be used during treatment.

45 SAMPLING RECOMMENDATIONS 3-5 days after remediation Same locations as pre-remediation (-supply) Can change Location >3 consecutive NDs. Every 2 weeks for 3 months Monthly for 3 months Quarterly for 1.5 years

46 POTENTIAL CONTROL ACTIONS Implement flushing program Hot water heater Operational deadlegs Monitor water Temp. Cl & ph Install point-of-use water heaters Test water for Legionella Implement periodic remediation program Install secondary disinfection system Install thermostatic mixing valves at outlets

47 Continuous Treatment Secondary Disinfection Systems Chlorine Chlorine dioxide Chloramine Ultraviolet light Heat Ozone Cu-Ag Ionization

48 Copper-Silver Ion Treatment System

49 Cooling Towers

50 COOLING TOWERS Cool water by heat of vaporization Responsible for epidemic outbreaks Transmit bacteria 2 Mi. (most ) Operate Spring to Fall

51 Cooling Tower Operation

52 Closed Circuit Cooling Tower

53 Transmission via Cooling Tower to HVAC

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55 Biofilm & Scale

56 COOLING TOWERS Require Rigorous Maintenance Inspection Water Treatment Biocide dosing Filtration Corrosion control Descale Wisconsin Protocol Registration (NYC. NJ in the future)

57 ROUTES OF TRANSMISSION Adjacent Properties to a Source Within 0.6 Mi High Risk Establishments Long-term Care Facilities Senior Citizen Housing Health Care Facilities Dialysis Centers

58 LHD FOLLOW-UP PLAN? Maintain communication with facility Assure sampling results are distributed LHD NJDOH Schedule conference calls as needed Frequent and regular contact with facility CDC Case Report Form

59 SAFE LIMITS IN POTABLE WATER No known safe amount (ALARA) OSHA Technical Manual limits do NOT protect susceptible populations Assess preventive maintenance if detected in <30% of samples Remediate if detect in >30% of samples Local remediation at locations with >1 cfu/ml

60 Discussion & Questions