SINGAPORE - Three burning questions were addressed at the multi-ministry task force press conference on Friday (April 30) following the rise in community cases and two clusters involving Tan Tock Seng Hospital (TTSH) and an immigration officer at Changi Airport Terminal 1.

Q: Is there a link between the Immigration and Checkpoints Authority (ICA) officer's wife and the cluster at the hospital?

A: Ministry of Health (MOH) director of medical services Kenneth Mak said that so far, there has been no "obvious link" between the ICA officer's wife, who is Case 62583 and a nurse at TTSH, and the current cluster at the hospital.

"In terms of where she's gone, where she works, it doesn't appear as if it overlaps with the movement of patients or the other staff that we have now detected as part of this cluster in TTSH," said Associate Professor Mak.

However, he added that epidemiological investigations and contact tracing are still going on, and that "on an abundance of caution", the ward where the nurse had been is now locked down.

All staff and patients in that ward are also being tested, and studies are being carried out on those who test positive.

"This will provide additional data that will allow us to determine whether her source of infection in fact is linked to the same outbreak that we're seeing in TTSH," said Prof Mak.

He said that it may well be that the two clusters are distinct from each other, but added: "We're keeping an open mind and the investigations still continue."

Q: Where did the TTSH cluster originate, and how did the first person get infected?

A: Prof Mak said that as epidemiological investigations are ongoing, it is not yet known for sure who the first case in the TTSH cluster actually is, and where they might have become infected.

However, he added that the first infected person who presented themselves is a nurse who reported her mild respiratory symptoms immediately after developing them as a result of the protocols in place at the hospital.

As such, the authorities could detect the infection and start doing contact tracing and testing.

"But she may not be the original patient that was infected, nor the cause for other patients and staff to be infected as well. So we keep open the possibility that infection may have been introduced into the hospital by someone else," said Prof Mak, adding that the actual first case could "easily" be someone undetected thus far, who might turn up over the next few days of testing.

Q: Why was a patient with symptoms moved from one ward to another at TTSH?

A: Case 62561, a 57 year-old patient at TTSH, was initially in Ward 7D and then transferred to Ward 9D.

He developed a fever on April 16 but did not seek medical treatment. On April 18, he went to TTSH's emergency department after his fever persisted, and he developed a runny nose and cough.

He tested negative for Covid-19 and was subsequently put into Ward 7D. On April 20, he was transferred to Ward 9D.

The task force was asked why he was moved even after he displayed symptoms.

Prof Mak explained that the man had initially been placed in Ward 7D for observation. However, when a bed became available in the definitive care ward, 9D, he was then transferred there.

Prof Mak added that on "an abundance of caution", all staff and patients in Ward 7D are being tested for the virus, and so far none has turned up positive.

"So we continue to be vigilant and we continue to watch to see whether or not there will be more cases that come up through our testing exercise," he said.