36 Legionellosis

https://www.cdc.gov/legionella/index.html

CDC Legionellosis page

19 cases

Fewer than 5 deaths

100 % of cases were hospitalized

1.5 cases per 100,000 population


36.1 Epidemiologic Review

36.1.1 Disease Information

Overview: Legionellosis is a respiratory disease caused by the Legionella bacterium. It can cause a serious type of pneumonia called Legionnaire’s disease or the less severe illness Pontiac fever. Rarely, Legionella can cause infections outside of the lungs, such as heart or wound infections.

Symptoms: Common symptoms include cough, shortness of breath, fever, muscle aches, headaches, diarrhea, and confusion.

Transmission: Legionella bacteria are found in freshwater environments (e.g. lakes, streams). They are also found in man-made water systems. Transmission occurs when one inhales a small droplet of water contaminated with the bacteria. Less commonly, it occurs through aspiration of bacteria contaminated water.

Treatment: Antibiotics are the appropriate treatment option.

Prevention Prevention measures include minimizing growth of the bacteria within man-made water systems. This includes implementing and maintaining effective water management plans.

36.1.2 Demographics


Rates for <1, 1-4, 5-17, 18-29, and 30-49 years of age are not displayed due to low case counts.

Racial and Ethnicity demographic data are not presented due to low counts.


36.1.3 Outbreaks

No outbreaks were identified in 2023.

36.1.4 Monthly and Historical Comparisons



Data for Utah and the CDC were retrieved from the CDC’s Notifiable Infectious Disease Data Tables.

36.2 Key Things to Know

  • Risk factors include 17 cases (89%) age 50 years of age or older, 10 cases (52%) current or former smokers, (9) cases (47%) chronic heart disease, 9 cases (47%) with diabetes, 6 cases (32%) with immunosuppression.
  • Water exposures among cases include 16 cases (84%) with municipal water use, 6 cases (32%) with hot tub/pool use. All cases showered in their exposure period.
  • Cases also frequently identified home respiratory equipment use: humidifier, ventilator, nebulizer, CPAP, BiPAP, routinely use supplemental oxygen or other respiratory equipment- 6 cases (32%).
  • 100% of cases contracted Legionnaires’ Disease Syndrome.
  • 11% (2 cases) were presumptive healthcare-associated. Presumptive healthcare-associated Legionnaires’ disease definition: A case with ≥10 days of continuous stay at a healthcare facility during the 14 days before onset of symptoms.
  • 37% (7 cases) were possible healthcare-associated. Possible healthcare-associated Legionnaires’ disease definition: A case that spent a portion of the 14 days before date of symptom onset in one or more healthcare facilities but does not meet the criteria for presumptive healthcare-associated Legionnaires’ disease.
  • 47% (9 cases) required intensive care.
  • 63% (12 cases) reported overnight travel, and of those cases (83%) reported a hotel stay. Travel-associated Legionnaires’ disease (LD) definition: A case of Legionnaires’ disease in a patient who has a history of spending at least one night away from home (excluding healthcare settings) in the 14 days before onset of illness.
  • Commonly reported symptoms among cases include fever, cough, shortness of breath, diarrhea and confusion.