Dengue is still spreading along Orchard Road and the adjoining areas.
So far, 93 people have been infected in the Orchard Road cluster - making it the second-largest cluster in the country. More than half are workers at a construction site there.
Another 40 people have been infected in adjoining clusters in areas such as Oxley Road, Devonshire Road and Leonie Hill.
The situation has prompted the Orchard Road Business Association (Orba) to send circulars to its members urging them to take steps to prevent the breeding of the Aedes mosquitoes.
Across the island, the number of infections over the past two months topped 400 a week, in what is traditionally the "low" season for dengue as the weather gets cooler. Last week, 450 people were infected, with another 109 diagnosed since Sunday.
Infections for the year crossed the 20,000 mark this week. This is almost 50 per cent more than the previous high in 2005, when 14,209 fell ill.
About 5,000 people have been hospitalised for the viral disease so far this year, said a spokesman for the Health Ministry. Six have died.
At the height of the epidemic in June, weekly infections topped 800, and were largely concentrated in the eastern part of the country.
The first dengue case in Orchard Road was reported on Sept 25. According to the National Environment Agency (NEA) website, two larvae breeding spots in homes, eight in public areas and four in construction sites in the Orchard road cluster have since been found. The largest dengue cluster is in Bedok, with more than 150 cases.
The Orchard Gateway construction site was given a one-week stop-work order in late October when larvae were found there, to clean the place up. Despite more cases being reported, Mr Steven Goh, executive director of Orba, said "it is business as usual as the situation is under control".
"We wish to emphasise that the dengue cases are contained within the construction sites in the Somerset area specifically, and do not affect the rest of the precinct in general," said Mr Goh.
When asked what steps it has taken to try to stop the spread of dengue in the shopping belt, the NEA was not able to reply by press time.
But some retailers in the area have swung into action. A spokesman for Frasers Centrepoint said it has stepped up checks, "especially in areas with a potential for mosquito breeding such as washing areas and the rubbish disposal area". He added that the outbreak is unlikely to affect business.
A spokesman for No. 5 Emerald Hill Cocktail Bar, however, said its business has already been affected. Some regular customers no longer come with their families, he said.
Additional reporting by Carolyn Khew