Possible hospital-acquired Legionnaires' disease case at St. Paul's Hospital

Hong Kong's Centre for Health Protection is investigating a possible hospital-acquired Legionnaires' disease infection at St. Paul's Hospital after a 45-year-old female patient died earlier this month.

The immunocompromised patient with underlying illnesses was admitted to a single room on November 19 and discharged on November 26. Readmitted on November 28, she developed fever and pneumonia. A December 2 respiratory sample tested positive for Legionella pneumophila serogroup 1. She died from her pre-existing conditions on December 6.

Sixteen of 24 water samples collected from her initial admission floor tested positive for the same bacteria strain, with concentrations exceeding the action level for high-risk hospital water systems. Twelve environmental samples tested negative.

Given the patient's hospitalization timeline and test results, the centre cannot rule out a hospital-acquired infection. Twenty-eight other patients from the same floor are under medical surveillance, with no additional cases found.

The hospital has closed the affected floor's wards and will disinfect the water supply system. Water samples from the patient's residence are also being tested.

Legionella bacteria thrive in warm water between 20 to 45 degrees Celsius and can be found in various water systems. Infection typically occurs through inhalation of contaminated droplets.