FEHD releases sixth batch of gravidtrap indexes for Aedes albopictus in January
The Food and Environmental Hygiene Department (FEHD) today (February 4) released the sixth batch of gravidtrap indexes and density indexes for Aedes albopictus in January, covering 17 survey areas, as follows:
District
Survey Area
January 2026
Area Gravidtrap Index
Area Density Index
Central and Western
Sheung Wan and Sai Ying Pun
0.0%
N/A
Wan Chai
Happy Valley and Tai Hang
0.0%
N/A
Islands
Cheung Chau
0.0%
N/A
Kowloon City
Ho Man Tin
0.0%
N/A
Kowloon Tong
0.0%
N/A
Mong Kok
Mong Kok and Tai Kok Tsui
0.0%
N/A
Sham Shui Po
Cheung Sha Wan
0.0%
N/A
Sham Shui Po and Shek Kip Mei
0.0%
N/A
Wong Tai Sin
Wong Tai Sin West
0.0%
N/A
Yau Tsim
Tsim Sha Tsui and Yau Ma Tei
0.0%
N/A
North
Sheung Shui
0.8%
1.0
Tai Po
Tai Po West
0.0%
N/A
Kwai Tsing
Kwai Chung West
0.0%
N/A
Lai King
0.0%
N/A
Tsuen Wan
Sheung Kwai Chung
0.0%
N/A
Tuen Mun
Tuen Mun North
0.0%
N/A
Yuen Long
Hung Shui Kiu and Ping Shan
0.0%
N/A
Among the sixth batch of Area Gravidtrap Indexes covering 17 survey areas in January, all were below 10 per cent.
The FEHD has so far released six batches of gravidtrap indexes for Aedes albopictus in January 2026, covering 62 survey areas; most of the areas recorded 0 per cent, indicating that the distribution of Aedes albopictus mosquitoes was not extensive.
The eggs of Aedes albopictus can withstand long periods of desiccation and will hatch when the temperature becomes suitable and water is present. Members of the public should continue to take mosquito control measures during winter to eliminate mosquito eggs.
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 their 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 the water in flower vases and clear the water in saucers of potted plants at least once every seven days;
- properly cover all containers that hold water to prevent mosquitoes from accessing the water;
- properly dispose of articles that can contain water, such as empty lunch boxes and 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 (DF). After reviewing the present DF and CF vector surveillance programme, the FEHD has expanded the coverage for monitoring Aedes albopictus mosquitoes starting from 2026. The number of survey areas set up in the community has been revised to 62, with some survey areas renamed. Additional gravidtraps will also be set up at different locations across the territory to strengthen the monitoring of the breeding of mosquitoes. Under the present surveillance mechanism, the FEHD has set up gravidtraps in 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#).
Photo source: reference image
