Update on number of dengue fever cases

     The Centre for Health Protection (CHP) of the Department of Health today (May 18) reported the latest number of cases of dengue fever (DF), and again urged the public to maintain strict environmental hygiene, mosquito control and personal protective measures both locally and during travel.
 
     From May 4 to 17, the CHP recorded two confirmed DF cases and the patients had been to Thailand and Vietnam during the incubation period respectively.  
 
     As of yesterday (May 17), 21 cases had been confirmed this year, all of which were imported cases. The cases were mainly imported from Thailand (eight), the Philippines (six), Cambodia (two) and Vietnam (two).
 
     DF remains endemic in some areas in Asia. In Guangdong, there were 17 cases this year as of May 14. The latest figures for 2018 reveal that 10 446 cases have been recorded in Thailand, 979 in Singapore (since December 31, 2017) and 34 in Japan. In the Americas, the latest figures indicate that 90 858 and 7470 cases have been filed in Brazil and Mexico respectively in 2018.
 
     The public should take heed of the following advice on mosquito control:
 

  • Thoroughly check all gully traps, roof gutters, surface channels and drains to prevent blockage;
  • Scrub and clean drains and surface channels with an alkaline detergent compound at least once a week to remove any deposited mosquito eggs;
  • Properly dispose of refuse, such as soft drink cans, empty bottles and boxes, in covered litter containers;
  • Completely change the water of flowers and plants at least once a week. The use of saucers should be avoided if possible;
  • Level irregular ground surfaces before the rainy season;
  • Avoid staying in shrubby areas; and
  • Take personal protective measures such as wearing light-coloured long-sleeved clothes and trousers and apply insect repellent containing DEET to clothing or uncovered areas of the body when doing outdoor activities.

     To reduce the risk of infections spread by mosquitoes, apart from general measures,  travellers returning from affected areas should apply insect repellent for 14 days (DF) or at least 21 days (Zika virus infection) upon arrival in Hong Kong. If feeling unwell, seek medical advice promptly and provide travel details to the doctor. DEET-containing insect repellents are effective and the public should take heed of the tips below:
 

  • Read the label instructions carefully first;
  • Apply right before entering an area with 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*;
  • Apply sunscreen first, then insect repellent; and
  • Re-apply only when needed and follow the instructions.

* 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 concentration of DEET of up to 30 per cent.
 
     The public may refer to the CHP's tips for using insect repellents for details.