The number of dengue infections is shooting up again, prompting the authorities to step up inspections and warn contractors of stiffer penalties for allowing mosquitoes to breed.
The National Environment Agency (NEA) has in particular intensified checks for breeding in construction sites, seen as greater focal points this year for spreading infection.
It had inspected about 3,500 more sites by April than it did in the same period last year, an increase of 80 per cent. Breeding was found in 12 per cent of sites, up from 10 per cent last year.
It is also warning errant contractors that they could face longer stop work orders and prosecution.
During last year's record dengue epidemic, construction sites comprised just 5 per cent of breeding grounds, while homes made up 70 per cent.
It is not clear if the trend has shifted this year.
With 336 people infected with dengue since Sunday, the total for the week could hit 400 - higher than the peaks seen in 2011 and 2012. Numbers have risen steadily since the end of April.
And while it is still only half the number seen in the same period last year, when a raging epidemic infected more than 22,000 people, the wet weather could lead to further increases, since mosquitoes breed in standing water.
The country is also approaching the traditional peak season for dengue - June to October - when hotter days enable the insects to breed faster.
So far, one person has died after contracting dengue, in January. Last year, there were seven deaths from the disease.
There are currently two locations where the outbreak is most active: Hougang and the Farrer-Holland area.
In Hougang, there have been 75 cases so far.
Near Farrer Road, more than 120 residents of Leedon Heights have come down with dengue, with six diagnosed just last week.
NEA inspectors found 25 larvae breeding sites in homes, 10 in public areas and 11 at construction sites in the area.
Thirteen dengue clusters have been linked to construction sites so far this year, with more than 200 workers infected.
Last year, 43 clusters were linked to worksites, with about 500 workers taken ill.
Second Minister for the Environment and Water Resources Grace Fu said the authorities are concerned about the situation, and will continue to take "tough action" against contractors. She urged the industry to adopt regular measures such as fogging and checking of workers' temperatures.
"We are taking a very cautious stand... I think there's still a possibility of another round of dengue going through the country," said the minister yesterday during a visit to a Sengkang worksite operated by Tiong Seng Contractors.
The company was issued an 11-day stop work order by NEA in February - almost double the average length - after five workers contracted dengue.
Its director, Mr Andrew Khng, who has since put in place more regular checks and fogging, said: "It caused a lot of anxiety... it's a big worksite and it's very difficult for us to find such a small insect...
"We have done our level best and I think our new measures are effective."
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This article was first published on May 24, 2014.
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