July's area ovitrap indices showed an upward trend with Sheung Shui rising to 68.5% from 40% in June, the Food & Environmental Hygiene Department says.

Other areas with ovitrap indices over the alert level of 20% are Tai Po (61.8%), Yuen Kong (45.8%), Tuen Mun North (24.6%), Kwai Chung (25%), Mong Kok (24.1%) and Lai King (20.4%).

The ovitrap indices reflect the prevalence of Aedes albopictus, a mosquito vector for Dengue fever transmission.

It is anticipated that indices for the remaining 19 areas, with results still pending, may also be higher than those of June, the department's Pest Control Officer-in-Charge Yuen Ming Chi said.

In view of the rising indices, the inter-departmental anti-mosquito response mechanism has been activated in all districts. Government departments concerned, in addition to the regular weekly programme, have been stepping up mosquito control measures and increasing the number of operations to contain the mosquito problem.

From July 15 to 31 the department conducted 22,400 inspections, during which 22,700 potential breeding places and 3,400 breeding places were eliminated. Eighty prosecutions were made from January to July for detection of mosquito breeding places.

The ovitrap indices and information on anti-mosquito measures under the Anti-mosquito Weekly Inspection Programme are available on the department's website and through its hotline 2868 0000.