Over 9,000 dengue cases reported so far this year, largest cluster in Chai Chee

Anti-mosquito measures taken at Eastvale condominium in Pasir Ris include misting, a process in which a fine mist of water-based chemicals is sprayed onto a surface, typically on plants. ST PHOTO: KEVIN LIM
Action taken at Eastvale condominium include alerting cleaners to check for signs of water ponding. ST PHOTO: KEVIN LIM
Eastvale condominium's management also purchased sand granular insecticide, distributed it to residents and taught them how to use it. ST PHOTO: KEVIN LIM

SINGAPORE - Singapore is in peak dengue season, with 9,135 cases reported as of Aug 2 - about five times more than the total number of dengue cases reported in the same period last year.

The National Environment Agency (NEA) said on Monday (Aug 5) that peak dengue season in the Republic usually stretches from June to October, and that the surrounding region is also seeing a surge in dengue cases this year.

The agency added that in just one week ending on July 27, a total of 610 cases were reported here.

Nine people have died from dengue this year, as of July 20. The victims lived in various areas across the island, including Bedok, Ang Mo Kio, Geylang and Hougang.

Between January and June this year, about 60 per cent of the Aedes mosquito breeding habitats detected across the island were found in homes. This figure rises to 70 per cent in dengue cluster areas.

As of Aug 2, there were still 190 active dengue clusters around the island.

The largest such cluster is in Chai Chee, with 145 cases, while the second-largest cluster is currently located in Pasir Ris, which the NEA has labelled a high-risk area.

A total of 124 dengue cases have been reported in Pasir Ris Drives 3, 4 and 6, as well as Pasir Ris Street 41, since the area became a dengue cluster on June 11 this year.

But residents in the area are fighting back against the disease.

One estate doing so is Eastvale condominium, located in Pasir Ris Drive 3.Nine of its residents have fallen ill with dengue since June 11.

The condominium's managing agent Michael Chua said his team became "very concerned" after finding out the condo was in a cluster area in June, and decided to step up its anti-mosquito measures.

Action taken included alerting cleaners to check for signs of water ponding, teaching residents the importance of good housekeeping and anti-mosquito tips, and increasing the rate of misting to twice a week.

Misting is a process where a fine mist of water-based chemicals is sprayed onto a surface, typically on plants. This has a longer lasting effect than fogging as the chemicals remain on the areas that are sprayed, which prevents mosquitoes from resting, resulting in their eventual death.

The condo's management also purchased sand granular insecticide, distributed it to residents and taught them how to use it.

Eastvale condominium's management also purchased sand granular insecticide, distributed it to residents and taught them how to use it. ST PHOTO: KEVIN LIM

Ms Sally Tan, the condominium's treasurer, said the measures were worth the additional cost of around $750 a month, which was borne by the management.

She said: "Our residents include the old and the young... we will do our best to help them, to protect our community, and not let the disease spread elsewhere."

A resident there, homemaker Joewe Koh, 37, said she was initially worried for the safety of her children after discovering the neighbourhood was a dengue cluster.

However, she feels the management's efforts have paid off. She said: "In the past, whenever we went downstairs we'd get bitten... Nowadays, we don't get bitten at all, and we're very happy. We can go to the pool, to the playground, and we feel safe."

Though fogging and misting are common methods associated with fighting dengue, the NEA had previously pointed out that they are effective only if the chemicals come into direct contact with the mosquitoes.

It also noted that the "severe limitation" of mosquito fogging is that it also kills insects that prey on mosquitoes.

However, it said, fogging and misting are currently being used as there are no alternative methods available to kill adult infected mosquitoes.

Last year, Singapore's Dengue Expert Advisory Panel chairman Duane Gubler said there was a need to move away from "easy approaches" such as fogging and examine newer methods with more potential, such as introducing sterilised mosquitoes and using new pesticide compounds.

Last month, the NEA announced that Project Wolbachia, which involves the release of sterile male mosquitoes leading to mosquito eggs that cannot hatch, had achieved up to 90 per cent suppression of the urban Aedes aegypti mosquito population at study sites in Yishun and Tampines.

However, the project is still under research and has not been deployed in dengue clusters yet.

Additionally, it is not meant to be a substitute for regular vector control operations, such as comprehensive mosquito surveillance, source eradication of mosquito breeding habitats and spraying of insecticide where necessary.

The NEA said that these will continue to be Singapore's key strategies for dengue prevention and control.

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