NEA steps up efforts against dengue epidemic

SINGAPORE - The National Environment Agency (NEA) said that the dengue situation has worsened with weekly cases hitting a record of 820 and continues to be a major threat to Singapore.

As more cases are expected, NEA said it is ramping up its vector control manpower to speed up inspections and surveillance. To bring down the population of adult mosquitoes responsible for transmitting the virus, officers will be seeking residents' cooperation to apply ultra-low volume (ULV) misting and insecticide aerosol sprays.

Next month, the Ministry of Health (MOH) and NEA will also distribute mosquito repellents to households, starting with those residing in cluster areas.

MOH and NEA urged everyone to remain vigilant and perform the five-step Mozzie Wipeout to prevent mosquitoes from breeding in their homes.

There were 820 cases reported in the week ending June 8 - the highest recorded so far. To date, 9,421 cases were reported this year, surpassing the 8,843 cases reported in the 2007 epidemic.

Against the backdrop of Singapore's low population immunity, NEA said that the current epidemic is driven by the continued transmission of the virus with high epidemic potential.

The risk of dengue transmission is boosted by the current warm weather, which hastens the maturation of mosquitoes and shortens the incubation period of the virus in mosquitoes.

While the majority of clusters reported continue to be in the eastern part of the island, there has been a rise in the number of clusters in the west and northern parts.

This suggests that dengue transmission is intensifying in these areas. With the dengue situation potentially worsening in the weeks ahead, NEA will roll out the following three initiatives.

First, NEA will be recruiting 300 more officers in the next one to two months through the ongoing mass recruitment exercises.

This will supplement the current 850-strong vector control team. With the strengthened operational workforce, NEA will be able to inspect 100 per cent of premises in the dengue clusters within a week.

They will also be able to step up preventive surveillance checks in non-cluster areas.

Secondly, NEA vector control officers will step up the indoor application of insecticides to bring down the number of infected adult mosquitoes.

To supplement ULV misting, NEA officers will be equipped with new aerosol sprays to be applied in dark or shady corners of homes where mosquitoes are likely to rest.

The spray is co-designed by NEA's Environmental Health Institute (EHI) with the insecticide manufacturer. The insecticide is dispersed into an aerosol of fine particles using a specially-designed nozzle.

As the particles remain suspended for a longer time, they can spread over a larger area while increasing the chance of contact with the mosquitoes.

NEA encouraged home owners to allow its officers to conduct the spraying, because the high prevalence of individuals infected with dengue, including those undiagnosed, could lead to a significant percentage of mosquitoes infected with dengue.

Lastly, NEA and MOH will distribute some 1.2 million insect repellents to all households to help residents protect themselves from mosquito bites and thus break the chain of transmission.

NEA vector control officers and volunteers conducting house visits will distribute the repellents from July to August, starting from the major dengue cluster areas. NEA is also working with the Ministry of Education (MOE) to distribute the repellents to students once the schools reopen.

As the majority of breeding spots are still found in homes, NEA urged all residents to also join the national fight against dengue.

The Aedes mosquito breeds in artificial containers mainly found in homes, and its life-cycle averages seven days. Hence, all residents should do the Mozzie Wipeout together once a week to break the breeding cycle. The five-step Mozzie Wipeout is listed below.

i. Change water in vases/bowls on alternate days
ii. Turn over all water storage containers
iii. Remove water from flower pot plates on alternate days
iv. Clear blockages and put BTI insecticide in roof gutters monthly
v. Cover bamboo pole holders when not in use

Apart from doing the Mozzie Wipeout, everyone can also help to remind their family members and neighbours to join in the collective efforts.

Members of the public may check for updates, sign up for SMS alerts on, and join the Stop Dengue Now Facebook group ( to connect with other dengue prevention advocates.