SINGAPORE - Four new Covid-19 clusters have surfaced, one of which involves a Punggol Primary School cleaner with four cases and another at Westlite Juniper Dormitory with nine cases.

The other two new active clusters are linked to individual cases, each having three cases linked to it, the Ministry of Health (MOH) said in an update on Tuesday (July 27) night.

In total, there are currently 39 active clusters.

The Jurong Fishery Port cluster, which remains the largest cluster to date, stands at 902 cases.

MOH also said that Covid-19 self-test kits will be given to those who visited Teban Gardens Market and Food Centre as well as 216 Bedok Food Centre and Market.

This is an added layer of ring-fencing to identify cases and prevent further transmission of the virus, which was likely seeded by fishmongers who visited Jurong Fishery Port.

The collection of these test kits will run from Wednesday to Thursday at the residents' committee centres at those two locations.

In a separate testing update on Tuesday, MOH also said it has concluded Covid-19 testing at four Housing Board blocks in Sims Avenue on July 24.

They are blocks 842, 844, 846 and 848, which are located near Geylang Serai Market. All 1,126 individuals tested negative.

Mandatory Covid-19 testing was done after viral fragments were detected in wastewater samples collected from the blocks.

The agency previously said it was investigating likely Covid-19 transmission at those blocks.

Residents, visitors and those who have interacted with residents as well as owners and staff of commercial units at those blocks were tested.

Singapore reported a total of 136 new locally transmitted cases, of which 55 were new unlinked cases. The total number of new cases on Tuesday is 139.

Among the cases are three seniors aged above 70 who are unvaccinated or partially vaccinated, and are at risk of serious illness.

Of the confirmed cases, 545 of them are currently warded in hospital. Most are well and under observation.

However, 21 are seriously ill and require oxygen supplementation. Two are in critical condition in the intensive care unit (ICU).

Of these 23 cases, only one is fully vaccinated, but requires oxygen supplementation as she has underlying medical conditions.

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Thirteen of them are seniors above 60 years old, of whom 12 are completely unvaccinated or partially vaccinated and have fallen very ill, MOH said.

Over the last 28 days, 27 local cases required oxygen supplementation, were admitted to ICU or died.

Fourteen of them are unvaccinated, 12 are partially vaccinated and one is fully vaccinated.

The number of new cases in the community has increased from 642 cases in the week before to 967 cases in the past week.

The number of unlinked cases in the community has also increased from 46 cases in the week before to 182 cases in the past week, MOH said.

This article was first published in The Straits Times. Permission required for reproduction.