The Food & Environmental Hygiene Department urges people to step up anti-mosquito efforts as the monthly ovitrap index rose from 0.2% in March to 4.9% in April.

At the district level, area ovitrap indices of 31 locations have recorded positive indices, of which six have exceeded 10%, including Lai King (18.2%), Diamond Hill (17%), Wong Tai Sin Central (13%), Sheung Shui (13%), Yuen Kong (12.5%) and Fanling (11.5%).

The index for port areas also rose slightly from zero in March to 0.1% in April.

Although the ovitrap indices were still below the alert level of 20%, preventive measures cannot be relaxed, the department's consultant Dr Ho Yuk-yin said, adding the indices reflected the rising activity of Aedes albopictus, the mosquito that carries Dengue fever.

He expects the index to rise sharply next month, as the weather becomes warmer and damper, providing more favourable conditions for mosquito breeding.

He urged people to stay alert and adopt anti-mosquito measures.

For anti-mosquito information, visit the department's website or call 2868 0000.