The authorities have stepped up checks on worksites around Singapore, after a cluster of Zika cases was reported last week to have originated from a site in Sims Drive.
Minister of State for Manpower Teo Ser Luck, who visited the Sims Urban Oasis construction site yesterday, said he was glad to see that the operator had taken more precautions.
"We need all operators to reinforce their preventive measures right now to assure the community, the workers on the sites as well, that although the symptoms may be mild, we can't take anything for granted," Mr Teo told the media.
He added that his ministry has sent out an advisory to site operators and will step up inspections.
"For those who are a bit more negligent in this field, we will work with you but we may take action against you if you don't take preventive measures because it's a very serious issue," he said.
Thirty-seven cases of Zika were first discovered over the weekend to have originated from the same site, and another two surfaced on Monday. No new fever cases were found yesterday, said the site's main contractor Woh Hup.
A stop-work order was issued to the 23,900 sq m site last Saturday. Woh Hup construction manager Yong Jian Rong said the company is working closely with the Ministry of Manpower and the National Environment Agency on when the order can be lifted.
"We've briefed all our workers, sub-contractors, staff and anybody who's involved in the site based on reports on what the symptoms of the virus are and how to personally protect themselves," he said.
Besides fogging and misting the site, the contractor increased the number of mosquito traps from 50 to about 500. These are installed throughout the condominium site, along the perimeter and in the workers' dormitory.
Workers must have their temperatures taken twice a day, and have been given repellent sprays, mosquito patches, repellent bands or clips and arm coverings. Netting was added to dorm room windows.
Mr Yong said the workers' morale has been "okay" since news of the cases was reported. "We've been telling workers every day not to worry, and that if anything happens, the company will take care of your health and give you the full medical attention you need."
Some 490 workers - a mix of staff from Woh Hup and its sub-contractors - stay at the on-site dormitory. Those recovering from Zika are given separate rooms with Wi-Fi and have their meals delivered to them.
The workers who fell sick were from a mix of companies and dormitories. Several, including Mr Baskaran Murugan, 33, recovered from their symptoms before it was discovered they had the Zika virus.
Mr Murugan, who had a fever, headache and conjunctivitis two weeks ago, said he told his safety officer about his fever in the morning and was taken to a nearby clinic as soon as it opened. The doctor gave him two days' medical leave and medicine, while the company gave him several additional days of rest and vitamin C.
When asked whether he was afraid when he fell sick, he said he did not know it was Zika. "It was not difficult for me, it was just like a normal fever."
Contractors whose sites are not within the Aljunied cluster are also taking more stringent precautions in addition to measures that were already in place to combat dengue.
CHL Construction workplace safety and health officer Richard Teo said the company held a briefing yesterday for workers at all its sites to teach them about the symptoms of Zika. It also set up a buddy system to check workers for rashes and conjunctivitis, and implemented temperature checks.
Migrant Workers' Centre chairman Yeo Guat Kwang said in a statement that the group will scale up its outreach at dorms and popular areas in the coming weeks to remind workers and employers to be vigilant.
"Zika is generally a mild disease. Therefore there should be no reason for (workers') work tenure in Singapore to be affected," he said.