There is currently no evidence to suggest that symptoms associated with the Omicron variant of COVID-19 are different or more severe than those of other variants, or that current vaccines and therapeutics would be ineffective against the new variant, according to a news report citing Singapore's Ministry of Health (MOH).
Channel News Asia reported that the ministry said two more people infected with Omicron variant travelled through Singapore to Malaysia and Australia.
More data and further studies on Omicron are needed, the Ministry of Health said adding that it is expecting to see more such cases being reported globally in the coming weeks.
"Should the Omicron variant be more transmissible than Delta and become the globally dominant variant over time, it is a matter of time before it establishes itself in Singapore," the Ministry of Health said on Friday.
"But the additional measures will help to buy time to learn more about dealing with Omicron, and to continue with our booster programme to strengthen our collective resilience for better protection against this new variant."
Ministry of Health said it might need to introduce or adjust its measures "at short notice" in response to the "fluid" situation.
On Omicron infections transmitting through Singapore's Changi Airport, Ministry of Health said the first case travelled from Johannesburg on November 27 on a Singapore Airlines flight, and arrived here the same day for his transit flight.
The passenger then travelled to Sydney on another Singapore Airlines flight arriving on November 28.
The New South Wales Ministry of Health in Australia on Friday confirmed he was a positive case, the Ministry of Health said in a statement on Friday.
The man had earlier tested negative on November 24 before leaving South Africa, and had remained in the transit holding area at Changi Airport until his departure for Sydney, said the Ministry of Health.
The second traveller arrived from Johannesburg via Singapore Airlines flight on November 19, and was in the transit holding area until her departure to Malaysia the same day.
This case was earlier reported as Malaysia's first detected case of the Omicron variant.
At a briefing earlier on Friday, Malaysian Health Minister Khairy Jamaluddin said the traveller was a 19-year-old woman who is a student at a private university in Ipoh, Perak state in northern peninsular Malaysia, and had completed her COVID-19 vaccination.
On Friday night, Singapore's Ministry of Health said 15 passengers on board the flight had been identified as her close contacts, but none had entered Singapore or interacted with the community in the city-state, and all of them had remained in the transit holding area.
Contact tracing is ongoing for both cases, and there is currently no evidence of any community transmission from them, according to a report by The Straits Times citing the Ministry of Health.
Meanwhile, all travellers entering Singapore on vaccinated travel lanes (VTL) will soon have to take COVID-19 tests daily for seven days on arrival as the country tightens measures against the Omicron variant.
This means there will be additional swabs on top of the current requirement for a pre-departure test, an on-arrival polymerase chain reaction (PCR) test, as well as supervised antigen rapid tests (ARTs) on day 3 and day 7 of their visit.
The new testing requirement will take effect on December 6, 11.59 pm, the Ministry of Health announced on Friday. It will remain in place for four weeks "in the first instance" until 11.59 pm on Jan 2, 2022, the ministry added.
The additional tests - on days 2, 4, 5 and 6 - are self-administered and will be done using ARTs. Travellers must submit their results online using a link that will be sent to them via their declared contact details.
On days 3 and 7, the ARTs will be done in a supervised setting at a Combined Test Centre or Quick Test Centre.
"Day 3 is the median incubation period, and day 7 is the day of exit from this testing protocol," said the Ministry of Health.
"During this seven-day period, other than on days when they go out for their supervised tests, these travellers must test negative on their self-administered ART before going out for activities on that day," Channel News Asia said citing the Ministry.
This new testing regime will also apply to travellers arriving from Malaysia using the land VTL from 11.59 pm next Monday. These travellers already have to take a pre-departure test and on-arrival ART.
The new testing regime comes amid concerns over the new Omicron variant.
Singapore detected its first two cases earlier this week, when two imported cases tested "preliminarily positive" for the variant. The National Public Health Laboratory is conducting whole-genome sequencing to confirm the Omicron variant.
"We have also been closely monitoring studies on the sensitivity of ARTs to the Omicron variant," said the Ministry of Health.
"Preliminary validation by the manufacturers show that ARTs remain effective in detecting COVID-19 cases of the Omicron variant, and laboratories are doing further biochemical tests to confirm these results," it added.
"These initial results lend confidence that ARTs remain effective as a method of detecting COVID-19, including Omicron cases," the channel quoted the Ministry of Health.
Singapore reported 766 new COVID-19 cases and nine deaths linked to the coronavirus on Friday.
As of Friday, Singapore has reported 2,67,916 COVID-19 cases and 744 deaths linked to coronavirus since the start of the pandemic.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)