The Hong Kong Centre for Health Protection (CHP) of the Department of Health is investigating a case of Legionnaires’ disease (LD) affecting a woman aged 68.

Hong Kong/CIA
Hong Kong/CIA

The patient, with underlying illnesses, has presented with shortness of breath and myalgia since January 11 and was admitted to Queen Mary Hospital for management on the same day.

The clinical diagnosis was pneumonia and she is now in serious condition.

Her urine sample tested positive for Legionella pneumophila serogroup 1 antigen upon laboratory testing by the CHP’s Public Health Laboratory Services Branch.

Initial inquiries by the CHP revealed that the patient lived alone with no recent travel history. Investigations are proceeding.

This is the fourth LD case reported to the CHP this year. In 2014 and 2013, 41 and 28 cases were recorded respectively.

Legionnaires’ disease (LD) is an infectious disease caused by a type of bacteria called Legionella. The disease was named after an outbreak of chest infection occurring in a Legion Convention in USA in 1976. In Hong Kong, LD has been made a statutory notifiable infectious disease since March 1994.

Legionella bacteria are found in various environmental settings and grow well in warm water (20 – 45°C). They can be found in aqueous environment such as water tanks, hot and cold water systems, cooling towers, whirlpool and spas, water fountains and home apparatus that supports breathing.

People may get infected when they breathe in contaminated droplets (aerosols) and mist generated by artificial water systems. They may also get the infection when handling garden soils, compost and potting mixes.

The disease is not transmitted by person-to-person contact, eating or drinking.