Just last year alone, the National Environment Agency (NEA) conducted one million inspections for mosquito breeding here, it said yesterday.

Despite this, there were 3,285 dengue cases reported last year, a 20 per cent jump from 2017.

The number of dengue cases has also increased over the past three consecutive weeks, with 207 cases reported last week, said NEA in a media release yesterday, highlighting its concern about a possible surge in dengue cases this year.

The agency said it conducted 1.2 million inspections each in 2016 and 2017.

NEA said one main reason for the increase in dengue cases last year was the increase in the Aedes aegypti mosquito population.

It went up by about 40 per cent last month compared to December 2017.

NEA said last year's inspections uncovered about 18,000 mosquito breeding habitats.

About 9,000 checks were conducted at construction sites, and 4,100 households were fined for mosquito breeding.

There were also about 500 court summons and 40 stop work orders issued to the construction sites, and 25 court prosecutions were also made against contractors for repeat offences.

The agency added: "NEA will continue with these inspection and enforcement efforts in 2019. To safeguard public health, NEA will not hesitate to take contractors and residents to task for mosquito breeding found at their premises.

"In particular, NEA will take strong enforcement actions against recalcitrant errant premises owners."

NEA added while there was no signal for a major outbreak, the increase in the Aedes mosquito population and the high number of dengue cases early this year may lead to a surge in numbers.

NEA said it has deployed about 50,000 Gravitraps islandwide. The surveillance system has detected an increase in the number of Aedes aegypti mosquitoes.

Aedes aegypti is the main vector of dengue in urban areas, but zika, yellow fever and the chikungunya viruses can also be transmitted by the same mosquito vector.

NEA said the public can protect themselves from mosquito bites by applying repellent regularly.

Those showing symptoms should consult a doctor early.

The latest updates on the dengue situation can be found on NEA's website, the Stop Dengue Now Facebook page and the myENV app.