SINGAPORE - For a second day running, Singapore recorded another daily high of new coronavirus cases, 728, with the total number of people infected crossing the 4,000 mark.

Like in the past two weeks, foreign workers living in dormitories continue to drive this increase, accounting for 654 of new patients. This means the total number of patients who have tested positive for the virus linked to dormitories now stands at 2,689, or three in five of all cases.

Of the remaining new cases, 48 are other local community cases while 26 are work permit holders living outside dormitories.

There were five new clusters announced linked to dormitories, the Ministry of Health (MOH) said in its daily update on Thursday (April 16).

They include two large purpose-built dormitories, Westlite Mandai, which is linked to 31 patients, and The Leo dormitory in Kaki Bukit, which has 21.

The remaining three new clusters are linked to factory converted dormitories: SJ Dormitory in Woodlands; 17 Sungei Kadut Street 4; and Grandwork Building in Sungei Kadut.

This means that 19 of the 43 purpose-built dormitories here, together with several factories converted into dormitories, have reported active clusters in recent weeks.

S11 Dormitory @ Punggol, Singapore’s largest cluster, added 181 cases as of noon on Thursday, and now has 979 cases – about a fifth of the country’s total.

Another dormitory, Mandai Lodge I, had another 154 new cases. Some 160 workers who live there have now tested positive for the coronavirus.

It said 19 per cent of the new cases are currently unlinked and contact tracing for these cases is being done.

No imported cases were reported for the seventh successive day.

Singapore now has 4,427 Covid-19 cases.

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As of noon on Thursday, 31 more patients were discharged from hospitals or community isolation facilities, bringing the total number of those who have fully recovered to 683.

The number of people who have died stayed unchanged at 10.

A third nursing home was also hit by the virus, with an 89-year-old resident, dubbed Case 4,053, at Pacific Healthcare Nursing Home now warded in an isolation room at Ng Teng Fong General Hospital. She tested positive for the coronavirus on Wednesday.

The Senja Road nursing home's affected areas have been thoroughly cleaned and disinfected, and those who have had close contact with the resident will be quarantined, the Agency for Integrated Care said in a separate statement on Thursday.

Two other nursing homes - Vanguard Healthcare's Woodlands Care Home, as well as Lee Ah Mooi Old Age Home - have previously reported cases. The latter has been linked to two deaths, both 86-year-old female residents.

The MOH also gave an update on another public healthcare sector employee who was infected with the coronavirus.

The KK Women’s and Children’s Hospital administrative staff member is a 41-year-old woman who had not recently travelled to affected countries or regions.

Known as Case 3,431, she reported the onset of symptoms last Friday, and test results confirmed Covid-19 infection on Tuesday. She was warded at Sengkang General Hospital.

The patient had not gone to work after she developed symptoms.

The MOH added that it has closed two existing virus clusters, as there have been no more cases linked to them for the past two virus incubation periods, or 28 days - the Masjid Al-Muttaqin cluster and Church of Singapore (Bukit Timah) sub-cluster.