The Republic is pushing back in the fight against dengue, with a 20 per cent drop in cases in recent weeks.
About 84 per cent of the 2,253 clusters reported this year were also closed as at the end of last month, said Minister for Sustainability and the Environment Grace Fu yesterday.
These include the large clusters in Bartley Road, Tampines Avenue 7, Cassia Crescent, Dakota Crescent, Leicester Road, Potong Pasir Avenue 1 and Braddell Road.
But Ms Fu cautioned in her written reply to parliamentary questions that the overall number of dengue cases still remains high, and that Singapore cannot afford to let its guard down.
Singapore is in its worst dengue outbreak, with 27,280 cases as at the end of last month. In contrast, the whole of 2013 - the year of the Republic's previous worst outbreak - saw 22,170 cases.
Ms Fu said many steps have been taken to fight dengue, including intensive enforcement and inspection regimes, which involved 107,000 inspections of homes, as well as the destruction of about 5,300 mosquito breeding habitats in May and June alone.
Aside from this, the National Environment Agency has partnered with various stakeholders and agencies to distribute more than one million bottles of insect repellent to students and residents in active dengue clusters, and suspected dengue patients.
Project Wolbachia has also shown promising results, said Ms Fu. This involves the release of male mosquitoes carrying the Wolbachia bacterium in certain areas of Singapore. Female Aedes aegypti mosquitoes that mate with such males lay eggs that do not hatch, thus suppressing the mosquito population.
Ms Fu said that the Aedes aegypti populations in Yishun and Tampines, two of the project's locations, have been suppressed by 90 per cent.
A preliminary analysis also found 65 per cent to 80 per cent fewer dengue cases at the study sites, compared with areas where Wolbachia-carrying mosquitoes were not released.
But, despite the success of the trials, Ms Fu said that Project Wolbachia is neither a "silver bullet" in the fight against dengue, nor is it ready for immediate deployment.
This is because effort is still needed to find innovations and engineering solutions to automate and sustain the mosquito production and release processes before the project can be implemented on a larger scale.
"More importantly, Wolbachia technology cannot replace the community's efforts to ensure good housekeeping, which will always be needed to keep our homes and estates free from mosquitoes and dengue," said Ms Fu.
She added: "The current conditions are challenging. We are still in the peak dengue season and an all-out national effort is necessary to win the battle against dengue...
"I urge all residents, especially those residing in dengue cluster areas, to do their part and take the three protective actions against dengue - spray insecticide in dark corners around the house, apply insect repellent regularly, and wear long sleeves and long pants."
Timothy Goh
