28,000 tested in effort to detect cases linked to TTSH cluster

Close to 28,000 people have been tested in the effort to detect cases linked to a Covid-19 cluster at Tan Tock Seng Hospital (TTSH), said Health Minister Gan Kim Yong in Parliament yesterday.

They comprise close to 12,500 people who may have been exposed to the cluster and volunteered to be tested, 12,000 TTSH staff and 1,000 patients, as well as close to 2,500 individuals who were quarantined following contact tracing.

Giving an update on the cluster, Mr Gan said that although the first detected case in the cluster was a staff nurse who developed symptoms of an acute respiratory infection on April 28 and dutifully reported them, she may not have been the first person to be infected who brought Covid-19 into the wards.

"Her responsible act enabled us to pick up the cluster at TTSH," he said, adding that investigations are still ongoing.

Of the 43 cases in the TTSH cluster, seven staff and two patients had received full doses of the Covid-19 vaccine, said Mr Gan, who is co-chair of the multi-ministry task force tackling Covid-19.

"They were all either asymptomatic, or exhibited only mild symptoms, and none of them required oxygen support," he noted.

Of the remaining 34 who were not fully vaccinated, six required oxygen, two are in intensive care and one has died of Covid-19 complications.

"While the numbers are too small to draw firm conclusions, the findings do indicate that vaccination provides critical protection even against Covid-19 variants," said Mr Gan, urging people to get vaccinated when the jab is offered to them, as well as to continue to comply with safe management measures afterwards.

"We know that while vaccination does not eliminate the risks of infection totally, it does provide significant protection against infections, and helps to reduce the severity of the disease. It is also likely to reduce onward transmission," he added.

He also outlined efforts made to contain and isolate the infections at TTSH, so that they do not spread to the larger community.

First, close contacts of the first detected case were quarantined, while everyone who could have been in contact with her were tested, including all staff and patients of the affected Ward 9D.

Testing and quarantine were also extended to all staff who worked in Ward 9D from April 20, as well as discharged and current inpatients and visitors to Ward 9D from April 20. This was the date that a patient - who started to display Covid-19 pneumonia symptoms around April 29 - had come into the ward.

Testing was also expanded to include all inpatients and all staff working in the main ward block.

Subsequently, all other TTSH staff were also screened and, as an additional precaution, patients and staff from the main ward block were retested.

An additional layer of defence was put in place, with discharged patients and visitors who were in the hospital during the affected period also invited to be tested. They were not close contacts and hence had a lower risk of infection, but they were offered testing out of an abundance of caution and to give them peace of mind, said Mr Gan.

For every case detected, those around them were tested and isolated, and all wards that had exposure to infectious cases were locked down.

"We will continue to monitor these individuals who have been exposed, and retest them where necessary as some of them may be incubating the infection," said the minister.

He added that TTSH has implemented a series of measures to prevent further spread within the hospital. It has stopped all new admissions to the hospital, restricted visitors, and reinforced the need for all staff to comply with infection control, hand hygiene and personal protective equipment regimes.