A 37-year-old woman is in serious condition with Japanese encephalitis, Hong Kong's second case this year.

The Centre for Health Protection said today the Tin Shui Wai woman developed fever, dizziness and double vision on July 20 and was admitted to Tuen Mun Hospital. As she did not travel in the month before the onset of the illness, the case is likely to be a local one, the centre's consultant Dr Thomas Tsang said.

Her three household contacts have no symptoms and have been put under medical surveillance. The centre will arrange health talks and blood-tests for nearby residents. It has set up a hotline (2575 1848) to provide health advice for people living in the surrounding area.

The Food & Environmental Hygiene Department has conducted vector surveys and mosquito control measures near the patient's home. Department consultant Dr Ho Yuk-yin said although the vectors that transmit the disease can be found in Hong Kong, the risk of an outbreak is slim.

Prevention tips are available on the centre's website and the Travel Health Service website.

Legionnaires update

Meanwhile, the centre has confirmed another imported case of Legionnaires' disease, bringing the year's total cases to seven.

The 35-year-old man developed fever, cough and shortness of breath on August 11 and was admitted to North District Hospital on August 16. He has recovered and was discharged August 26.

Dr Tsang said an analysis on the seven cases did not find any relation between each other. However, the patients - all males - are smokers or former smokers.

He said smokers over 50 are more vulnerable to the disease, and urged them to quit the habit.