Hong Kong will launch a six-week anti-mosquito campaign from Feb. 21, to strengthen the control of Japanese encephalitis vectors and Dengue fever prevention.

Hong Kong Food & Environmental Hygiene Department Community Medicine Consultant Ho Yuk-yin said Friday that a multi-pronged approach has been introduced to effectively prevent Japanese encephalitis.

Ho said enhanced efforts have been made to fight Japanese encephalitis vectors following the detection of five local cases last year.

Culex tritaeniorhynchus, a Japanese encephalitis vector, usually breeds in irrigation ditches, slow streams, ground pools, flooded fields and surface channels where emergent weeds and grass can provide shelter for the larvae.

"A multi-pronged approach has been introduced with special emphasis on five areas to effectively prevent the disease," Ho said. "These include Japanese encephalitis vector surveillance and information dissemination, mosquito control, publicity and public education, community participation and law enforcement."

The department has been conducting a comprehensive survey on local Japanese encephalitis vectors since October to identify their distribution.

Adult surveys on the vectors have been conducted around pig farms and wetlands where migratory birds are likely to be present, and larval surveys in illegal cultivation and vacant sites close to human dwellings. Mosquito specimens collected will be examined for the virus.

The survey has found Culex tritaeniorhynchus in a number of urban areas, including Central and Western District and Lam Tin, along with Sha Tin, Tsing Yi, Tai Po, Yuen Long, North District and Lantau Island.

"Though no larva and Japanese encephalitis virus were found since January, mosquito control has been stepped up in the areas concerned," Ho said.

"Information on the distribution of the Japanese encephalitis vector will be released regularly to the public and Government departments for necessary action."

On Dengue fever, Ho said although no local case was reported last year, people should stay alert as there were 31 imported cases.

"Government departments will play an active role in tackling the mosquito problem and solicit community support through their own networks," he said.

(Xinhua News Agency February 19, 2005)