Mosquito breeding has topped the 'high risk' level for dengue fever transmission, according to a survey that compared breeding levels to a World Health Organisation benchmark.
Mosquito eggs were found in traps in nearly 8 per cent of buildings in the government pilot study.
The WHO considers an area to be at high risk for dengue fever transmission if the percentage of houses infested with mosquito larvae tops 5 per cent, Food and Environmental Hygiene Department consultant Ho Yuk-yin said.
But Dr Ho said the 7.7 per cent mosquito breeding detection rate revealed by the study did not necessarily reflect actual conditions, since stagnant water in the flats was deliberately left unattended as part of the study.
He said it was hoped the public would have listened to the government's advice regarding mosquito prevention, such as emptying stagnant water from pot plant saucers regularly.
The study involved placing ovitraps - water-filled plastic cups - in 537 flats across Hong Kong.
