Legionnaires' Disease Outbreak in Hong Kong: Key Updates and Health Advice

Strategic Insights -

A recent spike in community-acquired Legionnaires' disease (LD) cases has been recorded in Hong Kong, with five cases reported between June 29 and July 5. The Centre for Health Protection (CHP) is conducting epidemiological investigations to identify potential sources of infection and high-risk exposure. As of July 5, a total of 78 LD cases have been recorded this year, with 135 and 121 cases reported in 2024 and 2023, respectively.

Key Takeaways:

  • Five community-acquired LD cases were recorded in Hong Kong from June 29 to July 5, with no epidemiological linkages established between these cases and other confirmed cases previously recorded in Hong Kong.
  • The cases involved individuals with underlying illnesses living in different districts, including Southern, Eastern, Sha Tin, and Tuen Mun.
  • Initial investigation revealed that all five cases are sporadic, with no common source of infection identified.
  • As of July 5, a total of 78 LD cases have been recorded this year, with 135 and 121 cases reported in 2024 and 2023, respectively.
  • Men, people aged over 50, smokers, and alcoholics are more susceptible to LD.
  • Poor maintenance of water systems, living in areas with old water systems, and recent stays in hotels or vessels are potential risk factors for infection.
  • The public is reminded to observe personal hygiene, not smoke and avoid alcohol consumption, and to regularly inspect, clean, and descale water taps and shower heads to prevent the growth of microorganisms.
  • The use of water filters is not encouraged, as clogging can promote the growth of microorganisms, and the filter needs to be changed periodically according to the manufacturer's recommendations.
  • Drain and clean water tanks of buildings at least quarterly, and seek and follow doctors' advice regarding the use and maintenance of home respiratory devices.
  • When handling garden soil, compost, and potting mixes, wear gloves and a face mask, water gardens gently, and avoid working in poorly ventilated areas.

Statistics:

  • Total LD cases recorded this year: 78 (as of July 5).
  • Total LD cases recorded in 2024: 135.
  • Total LD cases recorded in 2023: 121.
  • Susceptible groups: Men, people aged over 50, smokers, alcoholics, and those with weakened immunity.

Sources:

  • Hong Kong SAR Government. (2023). Code of Practice for Prevention of Legionnaires' Disease.
  • Hong Kong SAR Government. (2023). Housekeeping Guidelines for Cold and Hot Water Systems for Building Management of the Prevention of Legionnaires' Disease Committee.
  • Hong Kong SAR Government. (2023). Risk-based strategy for prevention and control of Legionnaires' Disease.
  • Hong Kong SAR Government. (2023). Legionnaires' Disease Page.