SINGAPORE – Dengue cases in 2023 fell by half compared with the first four months of 2022. According to the latest figures, there were 2,726 dengue cases from the beginning of 2023 to April 24. There were 5,651 cases over the same period in 2022.
No death was reported in the quarterly dengue-surveillance data published by the National Environment Agency (NEA) for the first three months of 2023.
The drop in cases comes in spite of the high number of dengue cases at the start of the year.
The 279 weekly cases in the first week of 2023 were the second highest for the first week in the last five years, driven by a high Aedes aegypti mosquito population and low population immunity against the prevalent dengue serotype-3 virus, said the NEA.
With warmer weather forecast for May to October, NEA is not ruling out a rise in dengue cases.
Warm weather spurs the growth of larvae and the dengue virus in mosquitoes.
Weekly dengue cases continue to remain above 100 since the beginning of the year, and NEA has worked with partner agencies and the community to close 92 per cent of 371 dengue clusters.
For these clusters, about two out of three Aedes mosquito-breeding sites were in homes, 26 per cent in public areas and 3 per cent in construction sites.
To shrink the population of Aedes mosquitoes in the community, the NEA has increased the production of male Wolbachia-Aedes mosquitoes, which will mate with female mosquitoes to produce eggs that will not hatch.
Since September 2022, Project Wolbachia has expanded its weekly production capacity from two million male mosquitoes to five million.
There are plans to further ramp up mosquito production and the number of Wolbachia mosquitoes released, even though NEA said that the process is labour-intensive as the Wolbachia technology is nascent, and off-the-shelf solutions to increase scale are not available.
In 2022, NEA conducted about 914,000 inspections for mosquitoes islandwide, uncovering about 23,800 mosquito-breeding habitats.
About 13,000 enforcement actions, including fines, were taken against owners of premises for mosquito breeding.
For construction sites, 900 fines and 129 stop-work orders were issued, and 88 contractors were charged in court for repeat offences.
