Over 9,000 dengue cases reported so far this year

An employee at Eastvale Condominium placing sand granular insecticide in a crevice. Anti-mosquito measures have been stepped up at the condo, located in a dengue cluster. A pest control officer carrying out misting on the premises of Eastvale Condomi
A pest control officer carrying out misting on the premises of Eastvale Condominium in Pasir Ris Drive 3 yesterday. Between January and June this year, about 60 per cent of Aedes mosquito breeding habitats detected across the island were found in homes, with the figure rising to 70 per cent in dengue cluster areas.ST PHOTO: KEVIN LIM
An employee at Eastvale Condominium placing sand granular insecticide in a crevice. Anti-mosquito measures have been stepped up at the condo, located in a dengue cluster. A pest control officer carrying out misting on the premises of Eastvale Condomi
An employee at Eastvale Condominium placing sand granular insecticide in a crevice. Anti-mosquito measures have been stepped up at the condo, located in a dengue cluster. ST PHOTO: KEVIN LIM

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

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

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

Between January and June this year, about 60 per cent of 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 last Friday, there were still 190 active dengue clusters islandwide.

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

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

But those in the area are fighting back. One estate doing so is Eastvale Condominium in Pasir Ris Drive 3. Nine of its residents have fallen ill with dengue since June 11.

The management decided to step up its anti-mosquito measures after finding out that the condo was in a cluster area in June.

 
 
 

Actions taken include alerting cleaners to check for signs of water ponding, teaching residents the importance of good housekeeping and increasing the rate of misting to twice a week. Residents were given sand granular insecticide and taught how to use it.

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

A resident, home-maker Joewe Koh, 37, said she was initially worried for the safety of her children after discovering the neighbourhood was in a dengue cluster. But the management's efforts have since eased her fears. "In the past, whenever we went downstairs, we'd get bitten. Nowadays, we don't get bitten... We can go to the pool, to the playground, and feel safe," she said.

Though fogging and misting are common methods associated with fighting dengue, the NEA previously said 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 still 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.

A version of this article appeared in the print edition of The Straits Times on August 06, 2019, with the headline 'Over 9,000 dengue cases reported so far this year'. Print Edition | Subscribe