SINGAPORE: A total of 437 residents of a National University of Singapore (NUS) hostel have been swabbed for COVID-19 in a special testing operation on Tuesday (Mar 23) after viral material was detected in a wastewater sample.
All results are currently pending, the Ministry of Health (MOH) said on Tuesday night.
Low levels of COVID-19 viral ribonucleic acid (RNA) were detected on Sunday from the National Environment Agency’s testing of wastewater sample collected on Saturday from the UTown Residence North Tower at NUS.
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“There is evidence to suggest that this may be due to viral shedding from a recovered past infection among the residents, but as a precautionary measure, MOH carried out special testing operations today to test residents of the affected apartments,” said the ministry, adding that 437 people were swabbed, excluding the recovered case.
In wastewater testing, samples of wastewater are collected from manholes, and the entire process can take between 30 minutes to three hours.
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Samples are then processed in the laboratory, and testing is conducted to detect whether SARS-CoV-2 material is present in the wastewater. SARS-CoV-2 is the virus that causes COVID-19.
NUS has implemented the wastewater surveillance programme for all hostels since December 2020, it said in a circular on Monday.
UTown Residence is a hostel for single and married graduate students, and can house up to 1,700 residents.