CHP Reports Two Legionnaires' Disease Cases, Urges Public to Maintain Water Systems and Follow Precautions

DH announces latest situation of Legionnaires' disease cases

The Centre for Health Protection (CHP) of the Department of Health today (January 5) reported the latest number of Legionnaires' disease (LD) cases, and reminded the public of the importance of using and maintaining properly designed man-made water systems, adding that susceptible groups should strictly observe relevant precautions.

From December 28 last year to January 3 this year, the CHP recorded two community-acquired LD cases. Both patients had underlying illnesses. The details of the cases are as follows:

• A 76-year-old female patient living in Eastern District; and

• A 66-year-old male patient living in Sai Kung District.

The CHP is conducting epidemiological investigations to identify potential sources of infection and high-risk exposure. Initial investigations revealed that these are sporadic cases. No epidemiological linkages have been established between the twocommunity-acquired cases and other confirmed cases previously recorded in Hong Kong.

One hundred sixty-seven LD cases had been recorded in 2025, while no LD cases had been recorded so far this year (as of January 3). In 2024 and 2023, there were 135 and 121 cases respectively.

Men, people aged over 50, smokers, alcoholics and persons with weakened immunity are more susceptible to LD. Some situations may also increase the risk of infection, including poor maintenance of water systems; living in areas with old water systems, cooling towers or fountains; using electric water heaters, whirlpool spas or hot water spring spas; and recent stays in hotels or ships.

Legionellae are found in various environmental settings and grow well in warm water (20 to 45 degrees Celsius). They can be found in aqueous environments such as water tanks, hot and cold water systems, cooling towers, whirlpool spas, water fountains, humidifiers and home respiratory devices that support breathing. People may become infected when they breathe in contaminated droplets (aerosols) and mist generated by artificial water systems, or when handling garden soil, compost and potting mixes.

Immunocompromised persons should:

• Use sterile or boiled water for drinking, tooth brushing and mouth rinsing;

• Avoid using humidifiers, or other mist- or aerosol-generating devices; and

• If using humidifiers, or other mist- or aerosol-generating devices, fill the water tank with only sterile or cooled freshly boiled water, and not water directly from the tap. Also, clean and maintain humidifiers/devices regularly according to manufacturers' instructions. Never leave stagnant water in a humidifier/device. Empty the water tank, wipe all surfaces dry, and change the water daily.

The public should observe the health advice below:

• Observe personal hygiene;

• Do not smoke and avoid alcohol consumption;

• Strainers in water taps and shower heads should be inspected, cleaned, descaled and disinfected regularly or at a frequency recommended by the manufacturer;

• If a fresh-water plumbing system is properly maintained, it is not necessary to install domestic water filters. Use of water filters is not encouraged as clogging occurs easily, which can promote growth of micro-organisms. In case water filters are used, the pore size should be 0.2 micrometres (µm) or less and the filter needs to be changed periodically according to the manufacturer's recommendations;

• Drain and clean water tanks of buildings at least quarterly;

• Drain or purge for at least one minute infrequently used water outlets (e.g. water taps, shower heads and hot water outlets) and stagnant points of the pipework weekly or before use;

• Seek and follow doctors' professional advice regarding the use and maintenance of home respiratory devices and use only sterile water (not distilled or tap water) to clean and fill the reservoir. Clean and maintain the device regularly according to the manufacturer's instructions. After cleaning/disinfection, rinse the device with sterile water, cooled freshly boiled water or water filtered with 0.2 µm filters. Never leave stagnant water in the device. Empty the water tank, keep all surfaces dry, and change the water daily; and

• When handling garden soil, compost and potting mixes:

• Wear gloves and a face mask;

• Water gardens and compost gently using low pressure;

• Open composted potting mixes slowly and make sure the opening is directed away from the face;

• Wet the soil to reduce dust when potting plants; and

• Avoid working in poorly ventilated places such as enclosed greenhouses.

The public may visit the CHP's LD page, the Code of Practice for Prevention of LD and the Housekeeping Guidelines for Cold and Hot Water Systems for Building Management of the Prevention of LD Committee, and the CHP's risk-based strategy for prevention and control of LD.

The Centre for Health Protection (CHP), Photo source: reference image

CFS urges public not to consume certain batches of powdered infant and young children formula

The Centre for Food Safety (CFS) of the Food and Environmental Hygiene Department today (January 6) said that, the CFS has been actively following up on Nestlé company's voluntary and precautionary recalls of certain batches of its powdered infant and young children formula in certain areas in Europe due to possible presence of Cereulide produced by Bacillus cereus in the individual raw material. The CFS has earlier conducted immediate follow-up investigation, contacted local importers (including Nestlé Hong Kong Limited (Nestlé HK)), retailers and relevant authorities. According to the latest information from Nestlé HK today, 21 batches of its powdered infant and young children formula imported into Hong Kong might have used the raw material concerned. As a precautionary measure, Nestlé HK has voluntarily stopped sales, removed from shelves the affected products and has initiated a precautionary recall.

Please refer to the Annex for product details of the 21 concerned batches of powdered infant and young children formula.

A spokesman for the CFS said, "Nestlé HK has initiated a recall of the affected batches of the products concerned. For enquiries about the recall, members of the public may call its hotline at 2599 8874."

The CFS, through its Food Incident Surveillance System, noted earlier that certain batches of Nestlé powdered infant formula were being voluntarily recalled in Europe due to possible contamination with Bacillus cereus. Upon learning of the incident, the CFS has immediately initiated follow up actions, published food incident posts to inform the public and the trade about the issue, and has been actively following up on the incident and enhanced surveillance.

Bacillus cereus is commonly found in the environment. Unhygienic conditions in food processing and storage may give rise to its growth. Cereulide is a heat-stable toxin produced in food by some strains of Bacillus cereus. Consuming food contaminated with excessive Bacillus cereus or its heat-stable toxins may cause gastrointestinal upset such as vomiting and diarrhoea.

The spokesman urged members of the public not to let infants and young children consume the affected batches of the products, and to seek medical treatment for infants or young children who felt unwell after taking the products concerned. The trade should also stop using or selling the affected batches of the products immediately.

"The CFS has alerted the trade and relevant department over the incident, and will continue to follow up and take appropriate action. Follow-up work is ongoing," the spokesman said.

Source: AI-found images