Yishun Community Hospital, where a new Covid-19 cluster was reported on Sunday, said yesterday that the infections broke out in a ward with 32 patients who are mostly above 60 years old.

A hospital spokesman said the ward's patients comprised those who have received one or both shots of the vaccine and others who are unvaccinated. All the patients in the ward, D98, are now under quarantine and visits to the ward have been stopped.

In reply to queries from The Straits Times, the hospital also said more than 300 staff members who had come into contact with the ward in the last two weeks have been tested, and all have returned negative results.

After the first patient tested positive for Covid-19 on July 30, all other patients in the ward, which provides sub-acute care and rehabilitation services, were also tested.

Three who were asymptomatic returned positive tests. The rest have been cleared.

As at Monday, the total number of patients linked to the cluster remained at four.

Further retesting will be done as an added precaution, the hospital added, even as investigations into how the cluster broke out are still ongoing.

The hospital said: "We have reached out to the families of the four patients to extend our assistance and support. We are making alternative arrangements for (all) affected patients to keep in contact with their families."

It added that all staff working in the ward must now wear full personal protective equipment. It said it has also reinforced the importance of adhering to strict infection control measures and safe management guidelines to its staff.

The cluster in the hospital comes amid efforts to get more senior citizens to go for their vaccinations. The Ministry of Health has repeatedly said that seniors are most at risk of developing serious symptoms if they get Covid-19, which the vaccine helps ameliorate.

More than 96,000 seniors, or 21 per cent of those aged 70 and above, have not booked a vaccination appointment, Parliament was told in an update yesterday.

Yishun Community Hospital is not the first hospital to see a Covid-19 outbreak on its premises. Changi General Hospital and Tan Tock Seng Hospital had both reported clusters.

In a commentary, ST's senior health correspondent Salma Khalik noted then that at least one public hospital had been lax with regard to visitors to its wards, allowing one in four of them to be in the ward without wearing a mask the whole time.