The monthly average ovitrap index for June rose to 20.7% from 15.1% in May, with the area ovitrap indices of Tsing Yi and Happy Valley reaching 55.6% and 50.9%, the Food & Environmental Hygiene Department says.

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

All the 38 areas surveyed last month recorded positive ovitrap indices, ranging 6.7% to 55.6%, with 18 areas having readings equal to or above the alert level of 20%. The inter-departmental anti-mosquito response mechanism has been activated in these districts. The Government departments concerned, in addition to the regular weekly programme, have been stepping up mosquito control measures in specific areas and increasing the number of operations to contain the mosquito problem.

As for port areas, the index also rose from 1% in May to 3.2% in June.

According to Hong Kong Observatory records, the total rainfall in June was 490.1mm, about 30% above normal. Although no local Dengue fever cases have been detected so far this year, the number of imported cases had risen to 14 as at July 20.

The public must stay alert to the threat of mosquitoes and strictly observe all anti-mosquito measures as the ovitrap indices can rise drastically under the current hot and wet weather.

More details about the ovitrap indices and anti-mosquito measures are available here, or call 2868 0000. For information on Dengue fever click here or call 2833 0111.