The Food and Environmental Hygiene Department (FEHD) announced today (May 23) that the monthly ovitrap index for Aedes albopictus for April rose to 1.8 per cent from 0.1 per cent in March, and reminded the public to keep up effective measures against mosquitoes as the summer weather is favourable for mosquito breeding.

     "Aedes albopictus is a kind of mosquito that can transmit dengue fever (DF) and Zika virus. In view of the fact that Hong Kong's first imported case of Zika Virus Infection this year was recorded last month and similar infection cases were reported in neighbouring areas where DF has also remained highly prevalent, and that with the advent of summer, the hot and rainy weather is favourable for proliferation of mosquitoes, the community must work with the Government to continue to carry out effective mosquito control measures," an FEHD spokesman said.

     Among the 52 areas surveyed, positive ovitrap indices were recorded in 23 areas, ranging from 1.6 per cent to 13.3 per cent, with the highest in Kwun Tong Central. As for the port areas, the monthly ovitrap index for Aedes albopictus for April rose to 0.5 per cent from zero in March.

     "The FEHD and relevant government departments will continue to intensify their mosquito prevention and control work covering areas under their purview, and strengthen publicity and education campaigns to remind the public to stay alert against the potential risk of mosquito-borne diseases, including DF and Zika Virus Infection. The FEHD will conduct a three-phase Anti-mosquito Campaign this year. The second phase of the territory-wide campaign, lasting for 10 weeks, was launched on April 24 and will end on June 30. During this period, mosquito prevention and control work is being enhanced by the FEHD and relevant government departments. The district offices of the FEHD have targeted areas which 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, and intensified mosquito prevention and control work at those places. The FEHD will, immediately after each phase of the campaign, conduct special territory-wide thematic mosquito prevention and control operations so as to enhance the effectiveness of the campaign," he added.

     As Aedes albopictus breeds in small water bodies, the spokesman reminded members of the public to inspect their homes and surroundings to remove potential breeding grounds, scrub vases and pot plant saucers at least once a week, properly dispose of containers such as soft drink cans and lunch boxes, and drill large holes in unused tyres. He also advised the public and estate management bodies to keep drains free of blockage and fill up all depressions to prevent puddles from forming. They should also scrub all drains and surface sewers with an alkaline detergent compound at least once a week to remove any mosquito eggs.

     In addition, rural areas and the vicinity of shrubby areas are the natural habitats for mosquitoes, other insects and animals. Members of the public living in rural areas may install mosquito screens on windows and doors if necessary. Those staying in the natural environment should take appropriate personal protective measures against mosquitoes, such as avoiding staying in the vicinity of shrubby areas for a long time, wearing light-coloured long-sleeved clothes and trousers and applying DEET-containing insect repellent. Members of the public are reminded to make reports to the government departments via 1823 if mosquito problems are detected.

     The spokesman reiterated that effective mosquito control requires the sustained efforts of all parties concerned. The community must work together with the Government to take effective mosquito control measures.

     The ovitrap index is divided into four levels, reflecting the infestation level of Aedes albopictus. Level 1 (< 5 per cent) indicates that infestation of the mosquito is not extensive in the area surveyed. Level 2 (5 per cent - < 20 per cent) indicates that infestation of the mosquito is slightly more extensive in the area surveyed. Level 3 (20 per cent - < 40 per cent) indicates that infestation of the mosquito exceeds one-fifth of the area surveyed. Level 4 (>/= 40 per cent) indicates that almost half of the surveyed area is infested with the mosquito. The Government will step up the scale of anti-mosquito operations according to the level of infestation as well as reports from front-line staff and the public.

     As Aedes albopictus can transmit DF and Zika virus, oviposition traps are set in 52 areas in Hong Kong for monitoring the breeding of Aedes albopictus, which is only one of the mosquito species commonly found in Hong Kong and is active only in the daytime. The index does not capture the activities of Aedes albopictus outside the 52 areas and it also does not measure the prevalence of other kinds of mosquitoes.

     The ovitrap indices for Aedes albopictus in different areas and information on anti-mosquito measures are available on the department website at www.fehd.gov.hk.

Ends/Tuesday, May 23, 2017
Issued at HKT 16:00

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