SINGAPORE, April 23 — The Ministry of Health (MOH) has detected 46 cases of the new “double mutant” Covid-19 strain of the coronavirus here that originated from India. This was the figure as of Tuesday (April 20) and all of the cases were imported.
Revealing these numbers on Thursday, MOH said in a statement that the new strain has not been detected within the community.
There is also no evidence that Westlite Woodlands dormitory residents who have recently tested positive for the coronavirus are infected with this new variant, Education Minister Lawrence Wong said. He was speaking as co-chair of the multi-ministry task force, which held a briefing for the media on Thursday.
In total, MOH said that it has detected seven Covid-19 cases here that have the B117 variant — also known as the United Kingdom variant — and one case of the B1351 variant, known as the South African variant.
Among these eight people, three of them were household contacts. Apart from these, there has not been any further spread within the wider community.
The one patient who has the South African variant works in the marine industry and was exposed to potentially infectious sources from ships visiting Singapore.
All of his close contacts, including dormitory and workplace contacts, have been placed on quarantine.
MOH said that “all necessary public health actions have been taken promptly to isolate and ring-fence these cases”.
As for imported cases, aside from the 46 cases who have the Indian variant, the ministry said that it has detected:
- 155 cases of the UK variant (B117)
- 130 cases of the South African variant (B1351)
- Six cases of the Brazilian variants (P1 B11281, P2 B11282, P3 B11283)
- Five cases of the B1525 variant
These patients have already been placed on stay-home notices upon arrival in Singapore, the ministry said.
Monitoring new variants, re-infected cases
During the multi-ministry task force briefing, a question was asked on how concerned the authorities are about the emergence of new variants, in particular the new “double mutant” variant from India.
In his reply, Associate Professor Kenneth Mak, director of medical services at MOH, said that the authorities are monitoring the situation very closely.
“There is emerging evidence that some of the viral variants of concern may have an increased risk of breakthrough. But yet, at the same time, for many other variants, this has not been seen in the data,” he said.
He added that the data for the Indian variant is still emerging, and the authorities are monitoring the situation closely to see whether this would be of concern in relation to travellers arriving in Singapore.
Separately, Assoc Prof Mak also said that the authorities are watching very closely the events of possible re-infection.
Though the majority of infected patients will develop an immune response that protects them from being infected again, Assoc Prof Mak noted that there have been studies showing that the levels of antibodies for some of these individuals have waned over time.
He added that two studies in Singapore have been done on groups of people here.
One was conducted by the National Centre for Infectious Diseases following recovered cases in the community, and a second one looked at workers staying in dormitories.
“We have demonstrated that in both groups, (the patients) retained an antibody response for a significant period of time, well above 300 days.”
Still, Assoc Prof Mak said that this antibody response does decline and it is possible for recovered patients to become re-infected with the coronavirus later.
Therefore, there is a need to remain vigilant as the recovered workers are reaching the 300-day milestone where their immunity may start to decrease, he said.
“It’s now prudent for us to start monitoring very closely for the risk of re-infection taking place, and this would be the basis for our enhanced posture for testing, not just among workers but also for travellers that come into Singapore.” — TODAY
