Written reply to Parliamentary Question on Project Wolbachia by Ms Grace Fu, Minister for Sustainability and the Environment

Written Reply by Ms Grace Fu, Minister for Sustainability and the Environment, to Parliamentary Question on Project Wolbachia, on 6 October 2020

Mr Chua Kheng Wee Louis: To ask the Minister for Sustainability and the Environment when will Project Wolbachia be extended to Sengkang town and the rest of Singapore to complement existing vector control strategies.

Answer:

1. The National Environment Agency (NEA) commenced Project Wolbachia in 2016 through a phased approach to rigorously evaluate the technology in the field.

2. A key challenge is that Wolbachia technology is nascent and does not have an off-the-shelf commercial solution for big scale application. NEA and its collaborators are innovating engineering solutions to scale up production and release sustainably and cost-effectively. For example, the male-female pupae sorter, developed by NEA and its collaborator Orinno Technology Pte Ltd, can sort pupae 10 to 20 times faster than the previous model. It uses a specially designed sieve, lighting and water-flow control, to achieve high accuracy and high efficiency separation of male pupae, female pupae and larvae. The deployment of Wolbachia technology to additional towns is contingent on the success of these efforts.

3. As such, while the initial results of Project Wolbachia in the Yishun and Tampines study sites are promising, we will need to conduct further trials to determine the optimal method in releasing mosquitos to achieve effective suppression. This is so that the Wolbachia technology can be sustainably deployed on a larger scale in the future. Since May 2020, NEA has also tested a more targeted release strategy in dengue high-risk areas of selected neighbourhoods in Choa Chu Kang and Bukit Batok towns, to pre-emptively suppress high Aedes aegypti mosquito populations in these areas. These trials are part of NEA’s efforts to explore alternative deployment strategies that are most suitable for the different urban landscapes in Singapore.

4. If the trials are successful, we will ramp up Project Wolbachia to cover the entire Tampines and Yishun towns by 2022, which is about 17% of all HDB estates and double the current area. We will start trials in landed housing estates. The selection of new areas for implementation will take into consideration the results of the trials in Tampines and Yishun towns, the mode of operations, NEA’s assessment of long-term dengue risk profile and other environmental factors.

5. Mosquito suppression technology like the use of Wolbachia is not a silver bullet and it cannot replace the community’s efforts to ensure good housekeeping, to keep our homes and estates free from mosquitoes breeding grounds. Comprehensive mosquito surveillance, source eradication of mosquito breeding, and comprehensive vector control efforts will continue to be Singapore’s key strategies for dengue prevention and control.