The monthly ovitrap index for August fell to 11.3% from 23.1% in July, the Food & Environmental Hygiene Department says.

Of the 38 areas surveyed last month, 37 recorded positive ovitrap indices ranging from 1.8% to 32.7%. For port areas the index fell from 2.9% to 1.3%.

Eight areas saw readings rise to the alert zone of 20% to 40% - Sham Shui Po East (32.7%), Tsing Yi (29.6%), Kwun Tong Central (27.6%), Wong Tai Sin Central (25.4%), Tai Wai (24.5%), Pokfulam (21.2%), Tin Shui Wai (20.8%) and Tseung Kwan O (20.3%).

The inter-departmental anti-mosquito response mechanism has been activated in these districts. Government departments concerned have strengthened inspections and stepped up efforts to enhance environmental hygiene conditions and eliminate existing and potential mosquito-breeding grounds in addition to the regular weekly programme.