July’s monthly gravidtrap index for Aedes albopictus drops significantly

image_pdfimage_print

     The Food and Environmental Hygiene Department (FEHD) today (August 14) announced that the monthly gravidtrap index for Aedes albopictus recorded a significant decrease from 16.4 per cent in June to 9.2 per cent in July, which was at Level 2, indicating that the distribution of Aedes albopictus in the areas surveyed was fairly extensive but dropped to a relatively low level.
 
     In July, among the 64 survey areas, only two areas (namely Sheung Shui, and the area of Shau Kei Wan and Sai Wan Ho) were recorded with the area gravidtrap index reaching the alert level of 20 per cent or above. The gravidtraps were mostly found in the vicinity of public and private residential areas, schools, recreational and sports facilities and public places. The FEHD has collaborated with relevant government departments and taken immediate action to strengthen mosquito prevention and control work in the above-mentioned areas.
 
     Moreover, the monthly density index for Aedes albopictus in July was 1.2, which represented that an average of 1.2 Aedes albopictus adults were found in the Aedes-positive gravidtraps, indicating that the number of adult Aedes albopictus was not abundant in the survey areas. The gravidtrap and density indices for Aedes albopictus in different survey areas as well as information on mosquito prevention and control measures are available on the department's website at www.fehd.gov.hk.
 
     A spokesman for the FEHD said, "The Government is very concerned about mosquito infestation. The FEHD has continued to intensify mosquito prevention and control work with relevant government departments in areas under their purview, including eliminating mosquito breeding places, applying larvicides, conducting fogging operations to eradicate adult mosquitoes, and placing mosquito trapping devices at suitable locations. The FEHD has also conducted site inspections with relevant departments, and provided them with professional advice and technical support to assist them in formulating and implementing effective anti-mosquito measures swiftly. At the same time, the FEHD has strengthened publicity and education. Under the concerted efforts and collaboration of various parties, the index in July recorded a significant drop. The FEHD will continue to monitor the mosquito infestation in all districts, and will conduct prompt and effective mosquito prevention and control work."
 
     The FEHD will conduct a three-phase Anti-mosquito Campaign this year. The third phase of the territory-wide campaign, lasting 12 weeks, was launched on August 7 and will run until October 27. During the period, the district offices of the FEHD will target areas that have drawn particular concern, such as public markets, cooked food centres and hawker bazaars, single-block buildings, streets and back lanes, common parts of buildings, village houses, construction sites, vacant sites and road works sites, to remove accumulated water and carry out mosquito prevention and control work. To further enhance the effectiveness of mosquito control, the FEHD and relevant government departments have also carried out the second phase of the All-out Anti-mosquito Operations since April 24 to focus on eliminating potential mosquito breeding places, and called on property management offices to arrange necessary repairs to their premises so as to minimise mosquito breeding places. Furthermore, intense adult control has been conducted by means of regular ultra-low volume fogging operations after the onset of the rainy season.
 
     The FEHD appeals to members of the public to 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, properly disposing of containers such as soft drink cans and lunch boxes, and drilling large holes in unused tyres. 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.
 
     Aedes albopictus is a kind of mosquito that can transmit dengue fever (DF) as well as Zika virus infection. DF is commonly found in tropical and subtropical regions of the world, and has become endemic in many countries in Southeast Asia. The dengue activity in neighbouring areas has remained high and Hong Kong has recorded 25 imported DF cases so far this year. Members of the public should stay vigilant and continue to carry out effective mosquito prevention and control measures.

Leave a Reply

Your email address will not be published.