Update on investigation into case of Legionnaires' disease

     The Centre for Health Protection (CHP) of the Department of Health today (October 2) reported an update on its investigation into a case of Legionnaires' disease (LD) announced on September 21.

     The case involves a 71-year-old male patient, who was admitted to Pok Oi Hospital (POH) on July 11 for underlying illness. He is now in a serious condition.

     Water samples and environmental swabs were collected from POH to test for Legionella in a joint investigation by the CHP and the Electrical and Mechanical Services Department on the possible source of infection and to support the implementation of control measures.
     Testing results revealed that the total Legionella count of one out of 14 water samples collected from the basin in the patient's bathroom was six colony-forming units per millilitre (cfu/ml), which was higher than the action level of water systems in low-risk areas of hospitals, i.e. one cfu/ml or above. All six environmental swabs tested negative for Legionella species.

     "Our epidemiological investigations show that the patient mainly stayed in the ward in POH in the entire incubation period. His respiratory specimen and the water sample from the basin in the patient's bathroom were of the same sequence type of Legionella pneumophila serogroup 1. Information so far has thus indicated that the patient had likely acquired LD in POH," a spokesman for the CHP said.

     "We noted that POH has conducted disinfection of the water systems concerned. The CHP has provided health advice against LD to hospital staff and in-patients, including those with weakened immunity who should use sterile or boiled water for drinking, teeth brushing and mouth rinsing," the spokesman said.

     "Medical surveillance in the ward to which the patient was admitted has been enhanced in collaboration with POH and no additional cases have been identified thus far. We will maintain close liaison with POH to monitor the latest developments. Epidemiological investigations are ongoing," the spokesman added.
     As of September 29, 79 LD cases had been reported in 2018. In 2017 and 2016, there were 72 and 75 cases respectively.

Ends/Tuesday, October 2, 2018
Issued at HKT 18:41