SINGAPORE — The dengue outbreak is not over yet, although the numbers have come down significantly, said Minister for the Environment and Water Resources Vivian Balakrishnan today (March 11).

Addressing questions from Members of Parliament during the ministry’s Committee of Supply Debate, Dr Balakrishan said the National Environment Agency (NEA) will deploy new tools to enhance its operations.

For example, Gravitrap surveillance systems which are deployed in Bukit Panjang and Clementi to trap mosquitoes and provide data on mosquito activity and viral prevalence will be progressively extended to other parts of the island, especially in cluster areas to complement other efforts to reduce the adult mosquito population.

Last year, dengue hit a historic high of 22,170 diagnosed cases — 50 per cent more than the last peak in 2005. Since the start of this year, there were an additional 3,075 cases.

Dr Balakrishnan said the outbreak last year was due to a dengue serotype switch from DENV-2 to DENV-1. This new strain of the DENV-1 virus, which Singapore has a low population immunity against, accounted for up to 85 per cent of all diagnosed cases, he added.

Construction sites are one particular area of concern for the authorities. Last year, 10 per cent of the 12,000 inspections conducted at construction sites were found to be breeding mosquitoes. Enforcement actions were meted out to these contractors, with fines totalling S$3.5 million. In the last six months, NEA has issued 55 stop-work orders, and prosecuted 26 contractors in court.

Contractors will need to strengthen their environmental management at their worksites as we will not hesitate to take action against any negligent contractor, Dr Balakrishnan said.