Legionella patient exposure management response

Legionnaires’ Disease and Transmission

Legionella bacteria are gram-negative, rod-shaped, aerobic bacteria that may cause Legionnaires’ disease when aerosols of contaminated water are inhaled. Patients at greatest risk of serious illness include those on immunosuppressant medication or with compromised immunity and those who smoke or have underlying medical conditions such as diabetes, chronic lung disease, kidney disease and some forms of cancer. Outbreaks have been linked to aerosol-producing devices such as air conditioning cooling towers, whirlpool spas, showers, decorative fountains, nebulisers, humidifiers, and water misters. Additionally, aspiration of contaminated water from ice has also been associated as a source of exposure. There is no evidence of person-to-person transmission of Legionnaires' disease.

Incubation Period

The incubation period for Legionnaires’ disease typically ranges from 2 to 10 days, averaging 5 to 6 days. However, outliers can range from 1 to 28 days, with a healthcare-associated case reported with an incubation period of 63 days.

Clinical Presentation

Symptoms of Legionnaires’ disease include fever, loss of appetite, headache, malaise, lethargy, and pneumonia. Some cases may also experience myalgia, diarrhoea, nausea, vomiting, and confusion.

Confirmed or Probable Healthcare Associated Cases

Definitions of confirmed or probable Legionella cases can be found in the Legionellosis – CDNA National Guidelines for Public Health Units.

If a person with a confirmed or probable case of Legionnaires’ disease has spent their entire exposure period in a healthcare facility, intensive investigations and management of identified problems must be undertaken. If the exposure period was partially spent in a healthcare facility, investigations should still be conducted to identify potential sources of exposure.

The investigation should include:

• Consideration of the person’s susceptibility to legionellosis
• Evaluation of potential environmental exposures whilst attending the facility and at external locations
• Prior history of cases associated with the facility
• Liaison with the water risk management team to identify if there were any issues regarding implementation of control measures and if other hazardous events occurred prior to the incubation period
• Review of previous water test results for Legionella.

Care of Patients

• There is no need for contact, droplet, or airborne precautions for patients suspected of having legionellosis.
• Visitors may continue to be allowed.

Incident Management Team

If a probable healthcare-associated case of Legionnaires’ disease is identified, convene an incident management team, including:

• Infection Prevention and Control Professional
• Infectious Diseases Physician
• Public Health Physician
• Building Engineering and Maintenance Service (BEMS) representative or water risk management team representative/s

Actions to control exposure

• Temporary measures should be implemented to manage exposure of vulnerable patients until the corrective actions on the water infrastructure have been undertaken and verified to have been successful. Some options to reduce exposure based on ceasing the use of suspected sources are listed below. Note that this is not an exhaustive list, and some may not be suitable for the healthcare facility.
  • Shower
    • Cease using suspected bathroom or outlet and install appropriate signage
    • Provide alternative bathing arrangements such as sponge bath or utilisation of other facilities that have tested negative for Legionella
    • Install medical filter heads on identified outlets (this should include any outlets that may share a thermostatic mixing valve)
  • Handbasin
    • Cease using the suspected outlet – install appropriate signage
    • Install medical filter head on identified outlet/s
    • Use low water flow (pencil stream) to avoid creation of aerosols if basin must be used
  • Equipment/medical devices (e.g. bronchoscopes, heater-cooler units or continuous positive airway pressure (CPAP) machines):
    • Remove any suspected equipment source from service until successful remediation has been achieved
  • Drinking water
    • Provide an alternative drinking water supply to vulnerable persons
• All temporary exposure control measures should remain in place until the absence of Legionella has been verified through follow up water testing or source has been identified. The incident management team are responsible for decisions regarding the continuation or discontinuation of the temporary exposure control measures.

Notifying Legionella detection

All prescribed facilities must notify the Department of Health within one business day if a prescribed test confirms the presence of Legionella in a sample of water used by the facility. Notification can be done by:

• completing the Legionella detection notification form
• emailing the form to legionella@health.qld.gov.au

For further follow the link - Notifying a Legionella detection Queensland Health

Water Risk Management Plan

All prescribed facilities (public sector hospitals, state aged care facilities and private health facilities licensed under the Private Health Facilities Act 1999) must have a water risk management plan that complies with section 61D of the Public Health Act 2005. Refer to the Water risk management in healthcare facilities Queensland Health.

Further Information

For more details, refer to Legionellosis – CDNA National Guidelines for Public Health Units Australian Government Department of Health and Aged Care