Speech by Mr Baey Yam Keng, Senior Parliamentary Secretary for Sustainability and the Environment, at the Opening Ceremony of the 7th Singapore International Dengue Workshop on 8 May 2023
Dr Rabindra Abeyasinghe, WHO Representative and Head of the WHO Country Office to Malaysia, Brunei Darussalam and Singapore
Dr Tran Thi Giang Huong, Director, Division of Programmes for Disease Control, WHO Western Pacific Region,
Dr Raman Velayudhan, Unit Head, Veterinary Public Health, Vector Control and Environment Unit, Department of Control of Neglected Tropical Diseases, WHO Geneva
Ladies and Gentlemen,
Good morning, and welcome to the 7th Singapore International Dengue Workshop. A warm welcome to our international guests, and those joining us online. I am heartened that the organisers of this workshop – the World Health Organization, Singapore’s Ministry of Foreign Affairs, National Centre for Infectious Diseases, and the National Environment Agency – have restarted this series of workshops after the COVID-19 pandemic. Since 2009, this workshop series has trained 326 public health practitioners from 45 countries in various aspects of dengue control, from surveillance to vector control to clinical management.
2 Today, we have more than 60 participants from 23 countries representing the WHO regions of Western Pacific, South-East Asia, Eastern Mediterranean, and Africa. Additionally, around 150 participants are joining the opening ceremony and lectures virtually, demonstrating our adaptability to broaden the workshop’s global reach using platforms developed during the COVID-19 pandemic. The knowledge and experiences all participants bring will undoubtedly be invaluable to the dengue control community.
3 Dengue is a major concern. With an estimated 390 million infections each year in over 125 endemic countries, it has caused suffering and strained healthcare systems. Though the disease can be mild for some, it can also lead to severe complications and deaths. Over 40,000 deaths are reported annually, many of whom are children. With new challenges arising from climate change, globalisation and urbanisation, the threat of dengue is escalating globally. WHO has reported a six fold increase in cases since 2000.
Singapore’s Dengue Experience
4 Dengue is endemic to Singapore and has been a public health threat since the 1960s. Our national dengue control programme emphasises environmental management, focusing on removing sources of stagnant water, improving solid waste management, and maintaining clean, litter-free public areas. The programme relies very much on the close collaboration with the community and other stakeholders. In addition, regular house-to-house inspections for mosquito breeding ensure high public awareness.
5 As a result, a person living in Singapore today is 10 times less likely to acquire a first-time dengue infection compared to the 1960s. However, this also means reduced population immunity to dengue.
6 There is currently one vaccine approved for use in Singapore, which is effective in protecting individuals who have had dengue before. However, because a large proportion of our population is dengue naïve, vaccination is currently not an effective strategy for containing dengue transmission. We will continue to monitor vaccine development as part of a multi-pronged approach for dengue control in Singapore.
7 With low population immunity, favourable climatic conditions for mosquito breeding, and the continued presence of dengue mosquitoes and viruses in the community, Singapore continues to face regular dengue outbreaks. In the last three years, Singapore experienced two large outbreaks – in 2020 with more than 35,000 cases and 32 deaths, and in 2022 with over 32,000 cases and 19 deaths.
8 The risk of a dengue surge remains high this year, with 2,944 dengue cases reported as of 5 May 2023. Although the overall risk of dengue is lower today than the 1960s, our experience highlights the need for continued sustained efforts to control the Aedes mosquito population in the community.
9 Aedes mosquitoes, which transmit dengue, also transmit chikungunya and Zika viruses, underscoring the need for robust mosquito control.
A New Chapter in Dengue Control
10 Significant advancements in novel vector surveillance and control tools have been made in the past decade. Singapore’s islandwide mosquito surveillance system, consisting of over 70,000 Gravitraps, monitors the dengue mosquito population across the country. Developed by the National Environment Agency (NEA)’s Environmental Health Institute (EHI), these traps provide us with a good geographical understanding of where the mosquito breeding hotspots are. This in turn directs vector control efforts and measure the effectiveness of these efforts. They also facilitate timely dengue risk information sharing with stakeholders and the public, spurring the community to proactively remove mosquito breeding habitats.
11 Under Project Wolbachia-Singapore, EHI is studying the use of male Wolbachia-carrying Aedes aegypti mosquitoes to suppress the urban Aedes aegypti mosquito population in the community. As the technology is novel and Singapore is the first to trial and implement this technology in a high-rise, high-density tropical environment, we tested various strategies and rolled out releases gradually in a phased approach. We have observed up to 98% suppression of the Aedes aegypti mosquito population at the release sites, and up to 88% fewer dengue cases in these areas.
12 Today, Project Wolbachia-Singapore benefits more than one million residents, covering about 30% of public high-rise residential blocks and 9% of landed private homes, across 13 sites. The technology is well received by the community, with 96% of residents in these areas expressing support for the project. We plan to expand the release of male Wolbachia-Aedes mosquitoes to more areas in the coming years. I understand that the organisers have planned for you to visit the Wolbachia-Aedes mosquito production facility, which will enable you to understand the scale and different dimensions of our work. We welcome your feedback and suggestions.
13 We are encouraged to see more interventions that could potentially combat dengue. Development of the Sterile Insect Technique, which relies on male mosquito sterility effected by radiation, is being supported by the International Atomic Energy Agency (IAEA) and tested in several countries. The Wolbachia replacement approach, championed by the World Mosquito Program, has also shown promising results in reducing the risk of dengue in Yogyakarta, Indonesia. This is indeed a new chapter for dengue control, with an array of tools that countries can choose from.
14 These innovative advancements are made possible through partnerships. Project Wolbachia-Singapore has received valuable support from WHO, IAEA, National Robotics Programme, Orinno Technologies, Verily Life Sciences, Saw Swee Hock School of Public Health, Nanyang Technological University, and University of Michigan. The years of exchanges among different programmes in the world have also accelerated the development of novel tools. We must continue with these collaborations and exchanges, so that these nascent tools are made more robust and cost-effective.
15 Today’s dengue workshop exemplifies the value of multi-sectoral collaboration in strengthening dengue control globally. We are encouraged by the participation of vector control managers, entomologists, virologists, clinicians, data scientists, communications experts, public health practitioners, and policymakers in this workshop – representing the many disciplines needed to work together to advance dengue management strategies. We also welcome the active involvement of nature groups, urban planners, engineering and technology companies, and pest control companies, in shaping the global dengue control strategy and landscape.
16 In conclusion, the increasing threat of vector-borne diseases and growing challenges and uncertainties we face today underscore the need for greater innovation and collaboration across sectors. This workshop provides an excellent opportunity to do just that – to exchange ideas, gain new insights, build connections, and strengthen linkages across different sectors in tackling dengue. I am confident that these efforts will be invaluable and go a long way towards enhancing global resilience to dengue.
17 On behalf of NEA, I also thank WHO for the close partnership we have had in providing training and promoting capacity building for integrated dengue management and control among WHO member states. This year’s redesignation of NEA’s Environmental Health Institute as the WHO Collaborating Centre for Reference and Research of Arbovirus and their Associated Vectors, marks 12 years of close collaboration between WHO and NEA. NEA is committed to supporting WHO’s efforts in strengthening the capacity and capability for the surveillance and control of arboviral diseases among member states. I am also grateful to MFA and NCID in partnering us in helping to strengthen this international cooperation.
18 I wish you all a very meaningful and productive week ahead. To our international guests, I hope you will find time amidst the heavy schedule to enjoy the sights and sounds of Singapore.