There have been 11 incidents of lapses in Covid-19 sample testing reported to the Ministry of Health (MOH) to date for further investigations.

This is out of a total of 3.68 million tests performed as at Oct 26, Health Minister Gan Kim Yong said in a written reply yesterday to a parliamentary question from Ms Cheng Li Hui (Tampines GRC).

Three of the 11 incidents were related to self-reported apparatus and equipment issues and had no impact on the test results, while another three were related to improper specimen handling, which caused a backlog or delay in test results.

The remaining five incidents were related to quality control and reporting lapses, which caused errors in test results.

"MOH was able to take quick actions to address any public health issues arising from these cases," said Mr Gan.

"MOH treats all incidents seriously and our investigations assessed them to be isolated events, and did not result from any systemic laboratory issues."

Mr Gan added that the ministry requires clinical laboratories to review their processes when such incidents occur, identify the root cause and take appropriate corrective and preventative actions.

He said the adequacy and appropriateness of each laboratory's review and actions taken are also assessed by MOH.

Mr Gan also addressed a question from Workers' Party MP He Ting Ru (Sengkang GRC), who had asked whether there have been any reported or suspected "long Covid" cases in Singapore.

This refers to reports that some Covid-19 patients overseas have experienced long-lasting, lingering symptoms even after they have recovered from the infection.

In his response, Mr Gan said that "long Covid" is currently not well defined and is the subject of ongoing studies.

"MOH has thus far not received any reports of 'long Covid'.

"However, our healthcare institutions are following their recovered patients closely to look for prolonged and lingering symptoms arising from Covid-19 as well as for late complications from the infection," he said.

"We will also continue to monitor the emerging findings on long-term effects of Covid-19."