Connecticut State Department of Public Health

Legionellosis

 

 

Information for Healthcare Providers

To assess possible common sources of exposure, staff of the Connecticut Department of Public Health (CT DPH), Epidemiology and Emerging Infections Program conduct follow-up on all confirmed legionellosis cases. Both the healthcare provider of record and patient are interviewed.

Healthcare-Associated Legionnaires' Disease

Exposure Categories for Surveillance Purposes - Defining Healthcare Facilities and Healthcare-associated Legionnaires’ Disease

Presumptive healthcare associated case: A case with ≥10 days of continuous stay at a healthcare facility during the 14 days before onset of symptoms.

Possible healthcare associated case: 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.

CDC recommends performing a full investigation to identify source of Legionella when:

≥1 case of presumptive healthcare-associated Legionnaires’ disease is identified at any time (a case with ≥10 days of continuous stay at a healthcare facility during the 14 days before onset of symptoms.

≥2 cases of possible healthcare-associated Legionnaires’ disease are identified within 12 months of each other (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).

The following details key elements of a full public health investigation to identify source of Legionella in healthcare facilities:

  1. Work with healthcare facility leaders
  2. Perform a retrospective review of cases in the CT DPH surveillance database to identify earlier cases with possible exposures to the healthcare facility
  3. Develop a line list of possible and definite cases associated with the healthcare facility
  4. Work with infection prevention and clinical staff to conduct active clinical surveillance to identify all new and recent patients with healthcare-associated pneumonia, and test them for Legionella using both culture of lower respiratory secretions on selective media, and the Legionella UAT
  5. Obtain postmortem specimens for culture, when applicable
  6. Consider recommendations for restricting water in the facility or other immediate control measures

  7. Perform an environmental assessment to evaluate possible environmental exposures to environmental sources of Legionella
  8. Perform environmental sampling, as indicated by the environmental assessment using a laboratory certified by the CT DPH Environment Lab Certification Program for Legionella analysis.
  9. Removal or decontaminate the potential  environmental source(s)
  10. Subtype and compare clinical and environmental isolates, if available
  11. Work with healthcare facility leaders to determine how long heightened disease surveillance and environmental sampling should continue to ensure the outbreak is over
  12. Work with healthcare facility leaders to review and possibly revise elements in the water management program, if indicated.
Epidemiologic Investigations

To assess possible common sources of exposure, follow-up is conducted on all confirmed legionellosis cases. Both the healthcare provider of record and patient are interviewed. Case-patients are interviewed using a standardized form. When an investigation is recommended in response to a healthcare-associated case, cluster or outbreak, a CT DPH multi-disciplinary team is convened.

The team may include staff from the CT DPH Epidemiology and Emerging Infections Program, Environmental and Occupational Health Assessment Program (EOHA), Drinking Water Section, Facilities Licensing and Investigations Section, and the Healthcare-Associated Infections and Antimicrobial Resistance programs.

Environmental Investigations

This team may review Centers for Medicare and Medicaid Services requirements to protect the health and safety of patients, the facility's overall Legionella water management program, and provide recommendations to conduct an environmental assessment relative to the healthcare-associated case, cluster, or outbreak. This includes environmental risk assessment, sampling, and evaluation of sampling results.

The environmental assessment may include a visual inspection of the premise plumbing and other water features like fountains, water sculptures, cooling towers, spa tubs, etc. The team may review water chemistry and physical parameter results in the past and present, taken at various points in the water distribution system. These water chemistry and physical parameters include water temperature, pH level, and residual disinfectant levels. 

 

 

This page last updated 2/21/2020.