Legionellosis Outbreak Associated with a Hotel Fountain Chicago
Legionellosis Outbreak Associated with a Hotel Fountain, Chicago 2012 June 11, 2013 Shamika Smith, MPH Epidemiologist City of Chicago Mayor Rahm Emanuel Chicago Department of Public Health Commissioner Bechara Choucair, M. D.
Legionellosis • Bacteria ubiquitous in environment, typically water • Transmitted through aerosolization or aspiration of Legionella-contaminated water • Immunocompromised individuals are most susceptible
Difference between LD and PF Legionnaires' disease (LD) Clinical features Pneumonia, cough, fever Pontiac Fever (PF) Radiographic pneumonia Yes Flu-like illness (fever, chills, malaise) without pneumonia No Incubation period 2 -14 days after exposure 24 -72 hours after exposure Etiologic agent Legionella species Attack rate < 5% > 90% Isolation of organism Possible Never Outcome Hospitalization common Case-fatality rate: 5 -30% Hospitalization uncommon Case-fatality rate: 0% CDC. Top 10 Things Every Clinician Needs to Know About Legionellosis. 2013. Retrieved from http: //www. cdc. gov/legionella/clinicians. html
Reported Legionellosis Case Counts, 1990 -2011* 3000 United States (CDC) 2000 1000 0 160 Illinois (IDPH) 120 80 40 0 50 40 Chicago (CDPH) 30 20 10 0 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 *Counts for U. S. (2011) not yet published.
Reported Legionellosis cases by month of onset, Chicago, 2001 - 2010 September 2006 N=12 Reported residences of cluster casepatients August 2007 N=14 June-Aug. 2010 N=18
Outbreak Identification • Aug. 14, 2012: Company A contacted CDPH reporting: --30 cases of respiratory illness --several cases of pneumonia; 1 death • CDPH contacted Hotel X-learned that guest (not Company A) also reported illness • Conference held at Hotel X from Jul. 30 - Aug. 3 -- Approximately 600 attendees -- Event I (7/30 -8/1): 427 people -- Event II (8/2 -8/3): 266 people -- 80 people attended both event
July and August Events Sunday Monday Tuesday Wed Thursday Friday Saturday JULY 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 AUG 1 2 3 4 5 6 7 8 9 10 11 12 13 14 CDPH notified 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
July and August Events Sunday Monday Tuesday Wed Thursday Friday Saturday JULY 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 AUG 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Water Closures 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
July and August Events Sunday Monday Tuesday Wed Thursday Friday Saturday JULY 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 AUG 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Water Closures 15 Water Drained 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Case Finding • Hotel reached out to guests 7/16 -8/15 --Earliest exposure date: 7/26 - 10 days= 7/16 --The day fountain, pool, spa drained: 8/15 • CDPH contacted other hotel event organizers • Hotel unable to obtain mailing addresses for ~40% of guests by 8/20 • Three press releases; media interviews
Methods: Survey Development • Exploratory interviews with Company A employees • Etiology unknown, therefore reviewed – Legionella questionnaire – CDC’s acute respiratory illness questionnaire • Piloted draft questionnaire, 8/15 (morning) • Questionnaire sent to all Company A hotel guests via Health Alert Network (HAN), 8/15 (afternoon)
July and August Events Sunday Monday Tuesday Wed Thursday Friday Saturday JULY 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 AUG 1 2 3 4 5 6 7 8 9 10 11 12 13 14 CDPH notified 15 Survey EPI-X 16 17 18 25 Sample 1 19 20 21 22 23 24 26 27 28 29 30 31
Methods: Environmental Health • Illinois Department of Public Health (IDPH), Environmental Health inspected/sampled: – Whirlpool spa – Indoor pool – Fountain in lobby – Locker rooms – Steam room – Sauna – Guest shower heads • CDC consulted
July and August Events Sunday Monday Tuesday Wed Thursday Friday Saturday JULY 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 AUG 1 2 3 4 5 6 7 8 9 10 11 12 13 14 CDPH notified 15 Survey EPI-X 16 17 Data analysis 18 Sample 2 Sample 3 25 Sample 1 19 20 21 22 23 24 26 27 28 29 30 31
Preliminary Data Analysis • Fountain exposure significantly associated with illness • Case definition: hospitalized, pneumonia dx, chest x -ray ordered Fountain Exposure Case Yes No Yes 13 7 20 No 51 99 150 64 106 170 P-value=. 0074
Number of calls received (N=250) Dates of press releases
HAN Survey Results and Data from CDPH Phone Bank HAN Survey from Company A • 328 responses, ~ 1/3 reporting illness • 1 confirmed case (1 expired) Phone Bank • 145 surveys completed, most reporting illness • 10 confirmed cases (2 expired)
Confirmed Legionnaires’ Disease (LD) Case definition: A person who stayed at or visited the hotel with illness onset within 2 -14 days of exposure to the hotel, AND with radiographically- or autopsyconfirmed pneumonia AND with laboratory evidence of Legionella infection.
Confirmed LD Laboratory Criteria • Isolation, through culture, of any Legionella organism from resp. secretions, lung tissue, pleural fluid, or other normally sterile site • Detection of Legionella pneumophila serogroup 1 (Lp 1) antigen in urine • Seroconversion (4 -fold increase in antibody titer to Lp 1 between acute and convalescent titers) • Detection by Lp 1 molecular testing (e. g. , PCR)
Suspect Legionnaires’ Disease Case definition: A person who stayed at or visited the hotel with illness onset within 2 -14 days of exposure to the hotel, who had radiographically- confirmed pneumonia, or clinical diagnosis of pneumonia, but without laboratory confirmation of Legionella infection.
Pontiac Fever Case definition: Fever, either subjective or documented, in a person who stayed at or visited the hotel with illness onset within 3 days of exposure to hotel, AND at least one of the following: cough, headache, SOB, myalgias, diarrhea, or vomiting, and who does not meet definition for confirmed or suspect LD.
Number of Cases Respiratory Illness by Date of Symptom Onset 25 (N=114) Legionnaires disease confirmed Legionnaires disease suspect Pontiac Fever Case fatality 20 15 10 CDPH notified Fountain, pool and spa drained 5 0 21 23 25 27 July 29 31 2 4 6 8 10 12 August 14 16 18 20 22
Case-patient Characteristics % Male All cases (N=114) Confirmed LD (N=11) 64 91 Median age (range) 47 yrs (22 -82 yrs) 65. 5 yrs (49 -82 yrs) % Hospitalized 13 82 Deaths 0 3 N/A Obesity (1), HIV (1), COPD (1), HTN/CVD (5), current/former smokers (2/2) Underlying illness/ risk
Case-patients’ Symptoms All cases Symptoms Confirmed LD (n/N) % Fever 113/114 99 10/11 91 Cough 76/110 69 9/10 90 Shortness of Breath 65/107 61 8/10 80 Vomiting or Diarrhea 57/105 54 5/11 45
Exposure Assessment (106 ills, 194 wells) Exposure # Exposed RR(CI) p Lobby Fountain 123 2. 13 (1. 64, 2. 77) <0. 0001 Lobby Bar 211 1. 25 (1. 09, 1. 44) 0. 003 Whirlpool Spa 5 2. 38 (0. 40, 13. 99) 0. 378 Pool 4 4. 76 (0. 50, 45. 10) 0. 302 Sauna 3 0. 79 (0. 07, 8. 63) 1. 000 Steam Room 4 1. 59 (0. 23, 11. 08) 0. 322 Guest Shower 236 1. 00 (0. 92, 1. 07) 0. 899 Guest Bath 50 0. 89 (0. 53, 1. 50) 0. 666
Environmental Results • Positive: Lobby fountain, locker rooms (men and women shower heads and sinks), swimming pool, whirlpool • Negative: Guest room shower heads
Matching Isolates • Lp 1 environmental isolates and a clinical isolate from a confirmed LD case-patient had matching sequence-based types.
Contributing Factors to Legionella Growth in Fountain • Lack of written cleaning and maintenance program • Presence of submerged lighting • Presence of dirt, organic matter, or other debris in the water basin
After Before
Remediation • Fountain removed • Installation of chlorine dioxide treatment system to water supply – Must keep monthly operational records – IDPH inspection every 2 years
Conclusions • Point source outbreak • Environmental testing identified Legionella in the hotel’s potable water system. • Poor fountain maintenance likely created favorable conditions for Legionella overgrowth • Epidemiologic and molecular typing data confirmed that fountain was likely the source
Acknowledgements • Centers for Disease Control and Prevention – National Center for Immunization and Respiratory Diseases, Division of Bacterial Diseases • Illinois Department of Public Health – Craig Conover, MD, MPH – Connie Austin, DVM, Ph. D – Division of Environmental Health – Division of Infectious Diseases
Acknowledgements • AL, AR, AZ, CA, CO, FL, GA, IN, KS, MA, MD, ME, MI, MN, MO, NC, NE, NJ, NY, OH, OR, PA, TN, TX, VA, WI, WV, Ireland, Canada • Chicago Department of Public Health – Communicable Disease Program – Emergency Preparedness Program
@Chi. Public. Healt h facebook. com/Chicago. Public Health 312. 747. 9884 Healthy. Chicago@Cityof. Chica go. org www. Cityof. Chicago. org/ Health
Public health Messaging • IDPH Environmental laboratory results • Exposures eliminated – Fountain removed – Pool, spa, locker rooms inaccessible to public • Updating case counts
Legionellosis cases by month of onset, 2011 -2012 20 Number of cases 15 10 5 0 JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
Reported 10 -year incidence rates per 100, 000 adult residents, by Chicago community area, 2001 -August 2010 Reported cases per 100, 000 adults Approximate reported residence of Chicago case-patients, with spatial clustering denoted in gray
Case-patients’ Characteristics All Cases (N=114) Confirmed LD (N=11) 64 91 47 (22 -82 yrs) 65. 5 (49 -82 yrs) % Hospitalized 13 82 Deaths 0 3 N/A Obesity(1), HIV(1), COPD(1), HTN/CVD(5), current/former smokers (2/2) % Male Median age (range) Underlying Illness/risk
Timeline Bakery re-opening Inspection and product recall Bakery closure 29 July = outbreak 30 3 1 August 12 18 22 23 30
Why the Increase? • Increasing population of older persons • Increasing population of persons at high risk for infection • Improved diagnosis and reporting • Weather conditions. .
July and August Events Sunday Monday Tuesday Wed Thursday Friday Saturday JULY 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 AUG 1 2 3 4 5 6 7 8 9 10 11 12 13 14 CDPH notified 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
July and August Events Sunday Monday Tuesday Wed Thursday Friday Saturday July 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 2 3 4 5 6 7 8 9 10 11 12 13 14 CDPH notified 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 1 August
July and August Events
July and August Events
July and August Events
July and August Events
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