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Legionnaires' Disease Prevention Port Waterborne Disease Management in Healthcare Settings Healthcare-associated Infections and Emerging Infectious Diseases Workshops January 28, 2020: Metairie February 4, 2020: Bossier City February 5, 2020: Lafayette “ The speaker does not have a financial or non-financial relationship with a commercial interest that would create a conflict of interest with this presentation. ” Disclosure Statement Objectives By the end of this presentation, attendees will be able to: Describe transmission, burden, and prevention measures Legionella pneumophila and Pseudomonas aeruginosa Describe a Water Management Plan Legionella pneumophila Gram-negative rod-shaped bacteria found naturally in the environment worldwide, usually in aquatic environments at least 60 different species, ~20 implicated in human disease Natural Habitat Occurs worldwide Prefers WARM WATERS with scale, sediment, metallic ions, and commensal flora Max multiplication from 25ºC to 45ºC (77-113F) Reduction at >50ºC (122F) No growth above 58.8ºC (138F) Found in 1-30% of home hot water systems Transmission Generally is not present in sufficient numbers in environment to cause disease Inhalation of water contaminated with Legionella aerosols generated by cooling towers, showers, faucets, spas, respiratory therapy equipment, and fountains Aspiration of contaminated potable water also proposed NO Person-to-person transmission Burden of Disease CDC estimates: 8,000 –18,000 cases in the U.S. annually 130-300 in LA Many infections not diagnosed or reported ~50 cases/year reported in Louisiana Class B reportable; 1 Business Day Reported Legionella Cases Louisiana, 1990-2017 Reported Legionella Cases and Incidence Rates per 100,000 Population Louisiana, 1990-2016 Burden of Disease 80% of reported cases are SPORADIC Outbreaks in hospitals, cruise ships, hotels, and other large buildings complex water systems Legionellosis Disease occurs in 3 forms: Legionnaires’ Disease (LD) Incubation 2-10 days Pneumonia illness accompanied by fever, cough, chills, myalgia, or respiratory failure 10% of people who get sick with Legionnaires’ disease die; 25% of healthcare associated cases Pontiac Fever (PF) Incubation 1-2 days; lasts 2-5 days Flu-like illness (fever, chills, malaise) without pneumonia Self-limiting, does not benefit from abx Extrapulmonary legionellosis (XPL) Disease outside the lungs (for example, associated with endocarditis, wound infection, joint infection) Risk Factors Recent travel with an overnight stay outside of the home, including stay in a healthcare facility Exposure to hot tubs Recent repairs or maintenance work on domestic plumbing Renal or hepatic failure Diabetes Chronic lung disease Systemic malignancy Smoking (current or historical) Immune system disorders Age ≥50 years Diagnosis Culture: Isolation of Legionella from respiratory secretions, lung tissue, pleural fluid, or a normally sterile site +Detects all species and serogroups +Clinical & environmental samples can be molecularly compared -Technically difficult & slow -May be affected by abx Urinary Antigen: Detection L. pneumophila serogroup 1 antigens in the urine +Rapid -Can only identify Lp1 -Cannot molecularly compare to environmental samples Diagnosis Nucleic Assay: detection of Legionella species by PCR Seroconversion: Four-fold rise in ab titer to Legionella by indirect immunoflourescent antibody assay (IFA) +Less affected by abx -1 elevated ab titer does NOT confirm case of recent Legionellosis: 5-10% of population have single acute titers ≥1:256 Healthcare Associated Cases Presumptive: Patient had 10 or more days of continuous stay at a healthcare facility during the 14 days before onset of symptoms. Possible: Patient had exposure to a healthcare facility for a portion of the 14 days prior to onset. Outbreak Definitions Dependent on the circumstances behind the cases exposure Travel-associated: CDC defines travel-associated outbreaks as two or more Legionnaires’ disease cases associated with the same travel accommodation in a 12-month period. Healthcare-associated: ≥1 case of presumptive healthcare-associated Legionnaires’ disease at any time or ≥2 cases of possible healthcare- associated Legionnaires’ disease within 12 months of each other Community-associated: You have identified one or more cases of Legionnaires’ disease at a correctional facility or other facility where people cannot leave the premises or you have analyzed available data and found an increase in Legionnaires’ disease in a certain geographic area Prevention Measures Grows poorly at < 20°C (68°F) and > 50°C (122°F) Killed at temperatures > 58.8°C (138°F) Susceptible to chlorine and bromine disinfectants, ozone, heavy metal ions, and UV light Nebulizer, respiratory therapy equipment: Use sterile water, do not let water stand, clean regularly Prevention Measures Hot water systems: flushing for >5min at temp > 65°C hyperchlorination but causes corrosion May grow back unless hot water maintained at ≥ 50°C but risk of scalding users cold water at ≤ 20°C residual chlorine at ≥ 1-2 mg/L of free chlorine remove scale and sediments www.menti.com Mentimeter Question #1 1. Go to www.menti.com on either your mobile device or computer’s web browser. What is the threshold of healthcare acquired 2. Use the code shown on the Legionellosis cases to be considered an outbreak? screen to participate in live polling for this activity. a) 1 presumptive healthcare acquired case 3. See results. b) 2 presumptive healthcare acquired cases Enter Code c) 2 possible healthcare acquired cases in 12 months d) 4 possible healthcare acquired cases in 12 months e) a&c f) b&d Pseudomonas Bacteria commonly found in soil and water Most common causing infection Pseudomonas aeruginosa Causes infections in the blood, lungs (pneumonia), or other parts of the body after surgery Transmission Live in the environment and can be spread to people in healthcare settings when they are exposed to water or soil that is contaminated with these germs. Person to person through: contaminated hands Equipment Surfaces Burden of Disease In 2017, multidrug-resistant Pseudomonas aeruginosa caused an estimated 32,600 infections among hospitalized patients and 2,700 estimated deaths in the United States Cases Over Time Who is at risk? Those most at risk include patients in hospitals, especially those: on breathing machines (ventilators) with devices such as catheters with wounds from surgery or burns Prevention Measures Patients and caregivers should: Keep their hands clean to avoid getting sick and spreading germs that can cause infections Wash their hands with soap and water or use alcohol-based hand sanitizer, particularly before and after caring for wounds or touching a medical device Remind healthcare providers and caregivers to clean their hands before touching the patient or handling medical devices Allow healthcare staff to clean their room daily when in a healthcare setting Water Management Plan Limits germ growth by: Keeping hot water temperatures high enough Making sure disinfectant amounts are right Keeping water flowing (preventing stagnation) Operating and maintaining equipment to prevent slime (biofilm), organic debris, and corrosion Monitoring factors external to buildings, such as construction, water main breaks, and changes in municipal water quality Water Management Plan - Components 1. Establish a water management program team Water Management Plan - Components 2. Describe the building water systems using flow diagrams and a written description Include details like where the building connects to the municipal water supply, how water is distributed, and where hot tubs, water heaters or boilers, and cooling towers are located. Water Management Plan - Components 3. Identify areas where Legionella could grow and spread Identify where potentially hazardous conditions could occur in your building water systems, such as areas where water temperature could promote Legionella growth or where water flow might be low. Healthcare facilities think about: Areas where medical procedures may expose patients to water droplets, such as hydrotherapy Areas where patients are more vulnerable to infection, such as bone marrow transplant units, oncology floors, or intensive care units Water Management Plan - Components 4. Decide where you need to apply control measures and how to monitor them. Establish control measures and limits for each hazardous condition, as well as plans for where and how to monitor them. Control measures are actions you take in your building water systems to limit growth and spread of Legionella, such as heating, adding disinfectant, or cleaning. Control limits are the maximum value, minimum value, or range of values that are acceptable for the control measures that you are monitoring to reduce the risk for Legionella growth and spread. Water Management Plan - Components 5. Establish ways to intervene when control limits are not met. Determine what corrective actions or contingency responses to take when control measures are outside of the control limits you established. Construction on a Daily flushing of floor both hot/cold water Increase frequency Documents all of temperature and activities chlorine monitoring Water Management Plan - Components 6. Make sure the program is running as designed and is effective. Verification: Are we doing what we said we would do? Validation: Is our program actually working? Update the program when necessary. Water Management Plan - Components 7. Document and communicate all activities. Document all the activities and communicate with building occupants, employees, and colleagues on a continual basis. If an event triggers you to review or update your water management program, remember to Update the flow diagrams, associated control points, control limits, and corrective actions Update the written description of your building water systems Train those responsible for implementing and monitoring the updated program Water Management Plan - Toolkit https://www.cdc.gov/legionella/downloads/toolkit.pdf Questions? Raychel Berkheimer, MPH Waterborne Disease Coordinator [email protected] 504-568-8307.
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