The Hong Kong Centre for Health Protection (CHP) has reported three additional cases of Legionnaires’ disease in recent days, bringing the 2015 total to date at 25.

This image shows Legionella colonies growing on a Petri dish. Image/Otto Schwake
This image shows Legionella colonies growing on a Petri dish.
Image/Otto Schwake

In 2014 and 2013, 41 and 28 cases were recorded respectively.

The first patient is 71-year-old man with underlying diseases. He presented with fever, cough with bloodstained sputum and shortness of breath since June 23. He attended the Accident and Emergency Department of Queen Mary Hospital on July 2 and was admitted on the same day. He was transferred to Grantham Hospital on July 6 for further management. His clinical diagnosis is pneumonia and his current condition is stable.

A second patient is a 69-year-old woman, also with underlying conditions. She presented with fever, cough and shortness of breath since July 3 and attended Pamela Youde Nethersole Eastern Hospital (PYNEH) yesterday (July 7) and was admitted to the Intensive Care Unit for further management. The clinical diagnosis is pneumonia and she is now in serious condition.

The most recent case reported today is a 67-year-old man with underlying illnesses. He  presented with fever, cough with sputum and shortness of breath since July 5. He attended the Accident and Emergency Department of Queen Elizabeth Hospital (QEH) on July 7 and was admitted on the same day. He was transferred to the Intensive Care Unit for further management on July 9. The clinical diagnosis is pneumonia and he is now in a critical condition.

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.

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