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FEHD releases fifth batch of gravidtrap indexes for Aedes albopictus in June (with photos)
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     The Food and Environmental Hygiene Department (FEHD) today (June 25) released the fifth batch of gravidtrap indexes and density indexes for Aedes albopictus in June, covering 31 survey areas, as follows:
 
District Survey Area June 2026
First PhaseGravidtrap Index First PhaseDensity Index
Central and Western Kennedy Town and Shek Tong Tsui 7.4% 1.5
Eastern North Point and Quarry Bay 6.8% 1.0
Southern Aberdeen and Ap Lei Chau 9.1% 2.8
Wan Chai Tin Hau and Causeway Bay 7.5% 2.5
Kwun Tong Kwun Tong Central 21.4% 1.2
Mong Kok Mong Kok and Tai Kok Tsui 0.0% N/A
Sham Shui Po Sham Shui Po and Shek Kip Mei 3.3% 1.0
Yau Tsim Tsim Sha Tsui and Yau Ma Tei 0.0% N/A
Sha Tin Tai Wai 0.0% N/A
Kwai Tsing Kwai Chung West 17.8% 1.0
Lai King 9.6% 1.0
Tsuen Wan Tsuen Wan Town 8.5% 1.4
Yuen Long Tin Shui Wai 18.0% 1.0
 
District Survey Area June 2026
Area Gravidtrap Index Area Density Index
Central and Western Sheung Wan and Sai Ying Pun 8.8% 1.9
Eastern Shau Kei Wan and Sai Wan Ho 14.3% 1.1
Southern Pok Fu Lam 13.3% 1.5
Wan Chai Happy Valley and Tai Hang 4.3% 1.2
Kowloon City Hung Hom and To Kwa Wan 7.9% 1.1
Kai Tak 9.4% 1.2
Sham Shui Po Cheung Sha Wan 29.2% 1.7
Wong Tai Sin Ngau Chi Wan and San Po Kong 11.1% 1.2
North Sheung Shui 10.0% 1.0
Sai Kung Sai Kung Town 11.3% 1.2
Tseung Kwan O East 3.4% 1.3
Tseung Kwan O North 12.9% 1.1
Sha Tin Ma On Shan 18.5% 1.1
Sha Tin East 8.9% 1.5
Tsuen Wan Tsuen Wan West 6.5% 1.0
Tuen Mun Tuen Mun South 7.3% 1.3
Yuen Long Hung Shui Kiu and Ping Shan 5.3% 1.0
Yuen Long Town 6.9% 1.0
 

     With reference to the data from the past few years, the gravidtrap indexes start to rise from April every year. The indexes are higher from May to June. The actual timing and extent of the rise are affected by factors like weather conditions and rainfall. As compared with last year, the temperature began to climb earlier this year and the rainfall in June increased substantially, creating favourable conditions for mosquito growth and breeding. Depending on factors like rainfall, the indexes may rise further, but the overall trend of gravidtrap indexes this year is similar to those of previous years.

     The FEHD has also carried out a series of actions, including:
  • conducting risk assessments to identify locations with more serious mosquito infestation, so as to carry out intensive and targeted mosquito control work, including stepping up inspections, eliminating mosquito breeding and potential breeding grounds, applying larvicides, conducting fogging operations to eradicate adult mosquitoes, and placing mosquito trapping devices at appropriate locations;
  • convening special meetings of the interdepartmental task forces on anti-mosquito work to co-ordinate relevant departments and stakeholders, such as construction site contractors, schools and property management companies, in strengthening venues' mosquito control work;
  • organising exhibitions with the relevant departments and stakeholders, and distributing leaflets and posters; and
  • notifying residential estates that have subscribed to the gravidtrap Rapid Alert System, advising property management companies and residents to stay vigilant and work together in taking mosquito prevention and elimination measures.

     During the follow-up actions and following the discovery of stagnant water or stagnant water containers at a construction site, a park, four public housing estates, four private housing estates and two private premises in Southern District, Kwun Tong District, Sham Shui Po District, North District, Sai Kung District and Yuen Long District, the FEHD has issued 12 statutory notices to the responsible persons-in-charge, requiring the clearance of such items within a specified timeframe.

     Public participation is crucial to the effective control of mosquito problems. The FEHD appeals to members of the public to continue to work together in strengthening personal mosquito control measures, including:
  • tidy up their premises and check for any accumulation of water inside the premises;
  • remove all unnecessary water collections and eliminate the sources;
  • check household items (those placed in outdoor and open areas in particular), such as refuse containers, vases, air conditioner drip trays, and laundry racks to prevent stagnant water;
  • change water in flower vases and scrub their inner surfaces thoroughly, and remove water in saucers under potted plants at least once a week;
  • properly cover all containers that hold water to prevent mosquitoes from accessing the water;
  • properly dispose of articles that can contain water, such as disposable meal boxes and empty cans; and
  • scrub drains and surface sewers with alkaline detergent at least once a week to remove any mosquito eggs.
     
     Starting in August 2025, following the completion of the surveillance of individual survey areas, and once the latest gravidtrap index and the density index are available, the FEHD has been disseminating relevant information through press releases, its website and social media. It aims to allow members of the public to quickly grasp the mosquito infestation situation and strengthen mosquito control efforts, thereby reducing the risk of chikungunya fever (CF) transmission.

     ​Following recommendations from the World Health Organization and taking into account the local situation in Hong Kong, the FEHD sets up gravidtraps in districts where mosquito-borne diseases have been recorded in the past, as well as in densely populated places such as housing estates, hospitals and schools to monitor the breeding and distribution of Aedes albopictus mosquitoes, which can transmit CF and dengue fever. At present, the FEHD has set up gravidtraps in 62 survey areas of the community, with a surveillance period of two weeks. During the surveillance period, the FEHD will collect the gravidtraps once a week. After the first week of surveillance, the FEHD will immediately examine the glue boards inside the retrieved gravidtraps for the presence of adult Aedine mosquitoes to compile the Gravidtrap Index (First Phase) and Density Index (First Phase). At the end of the second week of surveillance, the FEHD will instantly check the glue boards for the presence of adult Aedine mosquitoes. Data from the two weeks of surveillance will be combined to obtain the Area Gravidtrap Index and the Area Density Index. The gravidtrap and density indexes for Aedes albopictus in different survey areas, as well as information on mosquito prevention and control measures, are available on the department's webpage (www.fehd.gov.hk/english/pestcontrol/dengue_fever/Dengue_Fever_Gravidtrap_Index_Update.html#).
 
Ends/Thursday, June 25, 2026
Issued at HKT 18:30
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Today's Press Releases  

Photo

The Food and Environmental Hygiene Department (FEHD) today (June 25) released the fifth batch of gravidtrap indexes and density indexes for Aedes albopictus in June, covering 31 survey areas. Photo shows an FEHD staff member inspecting a park in Tin Shui Wai, Yuen Long District. Following the discovery of stagnant water inside the park, a statutory notice has been issued to the relevant venue management company, requiring the clearance of such stagnant water within a specified timeframe.
The Food and Environmental Hygiene Department (FEHD) today (June 25) released the fifth batch of gravidtrap indexes and density indexes for Aedes albopictus in June, covering 31 survey areas. Photo shows FEHD staff members conducting a fogging operation with a mechanical ultra-low volume fogger in the vicinity of Ma On Shan, Sha Tin District, to eliminate adult mosquitoes.
The Food and Environmental Hygiene Department (FEHD) today (June 25) released the fifth batch of gravidtrap indexes and density indexes for Aedes albopictus in June, covering 31 survey areas. Photo shows a staff member of the FEHD's contractor conducting a fogging operation to eliminate adult mosquitoes in the vicinity of Kwun Tong Central, Kwun Tong District.
The Food and Environmental Hygiene Department (FEHD) today (June 25) released the fifth batch of gravidtrap indexes and density indexes for Aedes albopictus in June, covering 31 survey areas. Photo shows staff members of the FEHD's contractor clearing drainage channels in the vicinity of Sheung Shui, North District, to prevent water accumulation and breeding of mosquitoes.
The Food and Environmental Hygiene Department (FEHD) today (June 25) released the fifth batch of gravidtrap indexes and density indexes for Aedes albopictus in June, covering 31 survey areas. Photo shows an FEHD staff member inspecting a public housing estate in Sai Wan Ho, Eastern District, and providing an estate management staff member with advice and technical support on mosquito prevention and control.
The Food and Environmental Hygiene Department (FEHD) today (June 25) released the fifth batch of gravidtrap indexes and density indexes for Aedes albopictus in June, covering 31 survey areas. Photo shows an FEHD staff member inspecting a public housing estate in Ngau Chi Wan, Wong Tai Sin District, and providing the estate management staff members with advice and technical support on mosquito prevention and control.