Cluster of cases of Legionnaires disease in Guildford area of Surrey

Public Health officials are currently investigating the cluster to identify the source of the bacteria.

Legionnaires’ disease is a pneumonia caused by Legionella. Legionella can grow and spread in man-made building water systems that aerosolize water like cooling towers, hot tubs that aren’t drained after each use, decorative fountains, and large plumbing systems.

Patients can get Legionnaires’ disease when they breathe in aerosolized water droplets containing Legionella. Most healthy people do not get Legionnaires’ disease from being exposed to Legionella. However, those at higher risk for developing pneumonia are the elderly, smokers, people with chronic lung conditions, and the immunocompromised.

Over the weekend, there were multiple media reports suggesting that the public seek medical attention especially if they have visited the Guildford area. Consequently, you may have patients present to you with concerns.

Testing for Legionella is not recommended for asymptomatic patients regardless of whether they were in the Guildford area or not. Consider testing patients for Legionella who are symptomatic with pneumonia-like symptoms (e.g., coughing, fever, shortness of breath, fatigue) and who indicate they have been in Guildford area 19 days prior to symptom onset.

Recommended testing for Legionella in symptomatic patients (order in addition to usual diagnostic testing as indicated for pneumonia):

Community out-patients: Legionella urine antigen testing
Hospitalized patients:

• Lower respiratory sample (e.g., sputum, bronchial washing, pleural fluid) for culture,
• Lower respiratory sample for nucleic acid testing, AND
• Urine antigen test for Legionella

For patients with pneumonia where Legionella is suspected, empiric antibiotic treatment should cover for Legionella (e.g., a fluoroquinolone, macrolide, or tetracycline).

Patients with suspected or confirmed Legionella infection do not require isolation or contact precautions. Person-to-person spread of Legionella is exceedingly rare with only one case reported in the literature. For laboratory-confirmed cases, Public Health will follow-up and get case histories on potential environmental exposures.

For patient information on Legionnaires’ disease, see the HealthLinkBC file.