Update on chikungunya fever
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     The Centre for Health Protection (CHP) of the Department of Health announced that as of 5pm today (October 22), no new cases of chikungunya fever (CF) had been recorded.

     So far this year, Hong Kong has recorded a cumulative total of 42 confirmed CF cases. All are imported cases. Among them, a 77-year-old male patient with chronic illnesses previously announced has passed away today after his condition deteriorated.  He returned to Hong Kong on October 13 from the Chinese Mainland and developed a fever and joint pain on the same day. He developed a rash on October 14 and sought medical attention at a private hospital where he was admitted for treatment. His condition subsequently deteriorated, leading to his transfer to the intensive care unit of Ruttonjee Hospital. The clinical diagnosis was CF complicated with multi-organ failure.

     Severe symptoms and deaths caused by CF are extremely rare, with a mortality rate of less than one in a thousand. The occurrence of severe complications is mostly related to the patients' underlying health conditions. Elderly persons (particularly those aged 65 or above), young children (particularly infants under one-year-old), pregnant women and persons with chronic illnesses (such as hypertension, diabetes or heart disease) are at higher risk of developing complications after contracting CF and may require a longer recovery period. Therefore, members of the public (especially the abovementioned high-risk groups) are advised to seek medical advice promptly if they develop relevant symptoms, particularly a fever, sudden severe joint pain and skin rash, after visiting areas affected by CF.

     Since the beginning of 2025, and as of September 30, a total of 445 271 suspected and confirmed CF cases and 155 CF-related deaths have been reported in 40 countries/territories. Cases have been reported in the Americas, Africa, Asia, and Europe. CF outbreaks currently occur in many countries worldwide. Members of the public should check the situation of the destinations before travelling abroad.

     The Food and Environmental Hygiene Department (FEHD) continues to conduct vector investigations and targeted mosquito control operations, and intensify mosquito prevention and control measures at the residences of recently confirmed patients, as well as at locations visited after the onset of symptoms. These measures include:
 
  • carrying out intensive fogging in scrubby areas within a 250-metre radius of the relevant locations to kill adult mosquitoes;
  • carrying out inspections of the locations, removing stagnant water, applying insecticides and disposing of abandoned water containers every week with a view to preventing mosquito breeding; and
  • enhancing public education efforts through organising health talks, setting up mobile education stations, and distributing publicity leaflets.

     The CHP urged schools to follow the FEHD's anti-mosquito guidelines to strengthen efforts to clear stagnant water on school premises and eliminate mosquito breeding sites. It is also imperative to remind staff members and students to consistently implement mosquito prevention and personal protective measures to guard against the spread of mosquito-borne diseases within school premises.

     Additionally, the CHP's Port Health Division continues to step up inspections at boundary control points and remind cross-boundary public transport operators and other relevant parties to ensure good environmental hygiene and effective implementation of anti-mosquito measures. Furthermore, staff members of the Port Health Division distribute leaflets to travellers, conduct temperature screenings for inbound travellers, conduct health assessments for travellers with fever or related symptoms and refer them to hospitals for follow-ups when necessary.

     Proper use of DEET-containing insect repellents or other effective active ingredients can prevent mosquito bites, but the following precautions should be taken when using them:
 
  • read the label instructions carefully first;
  • apply right before entering an area with a risk of mosquito bites;
  • apply on exposed skin and clothing;
  • use DEET of up to 30 per cent for pregnant women and up to 10 per cent for children (For children who travel to countries or areas where mosquito-borne diseases are endemic or epidemic and where exposure is likely, those aged 2 months or above can use DEET-containing insect repellents with a DEET concentration of up to 30 per cent);
  • apply sunscreen first, then insect repellent;
  • reapply only when needed and follow the instructions; and
  • in addition to DEET, there are other insect repellents available on the market containing different active ingredients, such as IR3535 and picaridin. When using any insect repellent, the public should follow the usage instructions and precautions on the product label.

     ​The FEHD also appeals to members of the public to continue to stay alert and work together to carry out mosquito prevention and control measures early, including inspecting their homes and surroundings to remove potential breeding grounds, changing water in vases and scrubbing their inner surfaces, removing water in saucers under potted plants at least once a week, and properly disposing of containers such as soft drink cans and lunch boxes. The FEHD also advises members of the public and estate management bodies to keep drains free of blockage and level all defective ground surfaces to prevent the accumulation of water. They should also scrub all drains and surface sewers with an alkaline detergent at least once a week to remove any mosquito eggs.

     The public should call 1823 in case of mosquito problems, and may visit the following pages for more information: the CF page of the CHP and the Travel Health Service, the latest Travel Health Newstips for using insect repellents, and the CHP Facebook PageInstagram Account and YouTube Channel, and also the Mosquito Prevention and Control dedicated page of the FEHD.

Ends/Wednesday, October 22, 2025
Issued at HKT 19:56

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