Over 70 per cent of Singapore's largest single-day surge in Covid-19 cases comprised people coming into Singapore from overseas.

The Ministry of Health (MOH) said yesterday that 33 of the 47 new cases confirmed were imported cases, with a large majority of them returning residents and long-term pass holders. Only three were short-term visitors.

Yesterday's numbers add to what has been a sharp increase in the number of imported cases in the past week. There were 101 cases from overseas in just the past week, compared with 34 in the nearly two months prior.

In total, 135 of the 313 cases in Singapore are imported cases.

The rising numbers are a re-flection of the global nature of the outbreak, Health Minister Gan Kim Yong said at a news conference yesterday.

Singapore should expect the number of imported cases to continue to rise, he said.

"We have to take into consideration what is happening to the rest of the world... Because we are connected to the rest of the world, even though we have travel restrictions, we have travel advisories, there will still be Singaporeans who will make necessary trips overseas and will (still) have a risk of importation."

Of the cases confirmed yesterday, a total of 11 patients had been to the United Kingdom, and seven to the United States. There were also cases with a travel history to India, Switzerland, Croatia, France, Germany, Austria, Thailand, the Philippines, Indonesia and Turkey.

Associate Professor Kenneth Mak, director of medical services at MOH, said: "It is clear that in terms of cases with travel history, the countries that our imported cases have an association with goes well beyond the countries we currently have travel restrictions on."

Of the locally transmitted cases, two are linked to the clusters at Church of Singapore (Bukit Timah) and boulder+ gym, while one is linked to the Masjid Al-Muttaqin cluster.

Six others are linked to previous cases, while contact tracing is taking place for another five.

Three more patients were discharged yesterday, bringing the total number of those who have recovered to 117. Of the 196 patients still in hospital, most are stable or improving, while 15 are in critical condition in the intensive care unit.

As of noon yesterday, MOH has identified 6,250 people who are close contacts of confirmed cases. Of these, 2,221 are still in quarantine.

LISTEN TO HEALTH CHECK PODCAST