Sec 1 student wrongly diagnosed as positive due to TTSH lab lapse

A Secondary 1 student from Jurong West Secondary School, who was told that she had Covid-19, has now been informed that it was a mistake.

Human error in Tan Tock Seng Hospital's (TTSH) laboratory - which the hospital has apologised for - led to the false diagnosis.

The 13-year-old student was reported last Friday to have tested positive for the coronavirus.

She was swabbed because she had been in contact with a schoolmate, a 13-year-old boy, who was previously confirmed to be infected.

With the latest findings, there is no second confirmed case in the school or student-to-student transmission, said Ms Liew Wei Li, the Ministry of Education's (MOE) director of schools.

All 71 students and staff who were the close contacts of the first case in Jurong West Secondary School have tested negative.

In a separate statement, the Ministry of Health (MOH) said that "due to a human error", the laboratory had mislabelled a swab sample from a Covid-19-positive individual as belonging to the student, without properly verifying the patient identifiers of the specimen tubes.

The error was discovered upon retesting of the student and the MOH was informed of the error on Monday.

After the first test, the student was admitted to the National University Hospital (NUH) where she was retested twice. Both test results came back negative.

The TTSH laboratory then repeated a polymerase chain reaction test on the original sample and the result was also negative.

Investigations showed that the mislabelled positive sample belonged to a migrant worker who had been isolated since his swab, and had not been in contact with any other individuals.

He is currently well, and has been admitted to the National Centre for Infectious Diseases.

The student, who had been isolated while at NUH, had not come into contact with other Covid-19 patients there and is, therefore, not at risk of infection from other patients in the hospital, the ministry added.

But since she was a close contact of her schoolmate who was infected earlier, she will continue to be in quarantine.

The MOH has, however, rescinded the quarantine orders of her close contacts who had previously been placed on quarantine.

Stressing that it takes a serious view of the lapse, the MOH said: "We are investigating this matter, and will take appropriate actions against the laboratory if it is found to be in breach of protocols."

Four students and a school teacher are among 20 newly confirmed community cases, says the Ministry of Health (MOH).

One of the students, a 13-year-old boy, is from Jurong West Secondary School.

All four students are linked to household infections and were on home quarantine orders before they were later swabbed as close contacts of their household members.

The MOH announces that a Secondary 1 female student from Jurong West Secondary School who had tested positive for the coronavirus is linked to the 13-year-old boy.

Since she was a close contact of the boy, she had been serving an MOH home quarantine order since July 6.

Tan Tock Seng Hospital says "human error" in its laboratory led to a false diagnosis, and subsequent re-tests found that the female student did not have the coronavirus.

The mistake came about when two patients had their specimens cross-labelled.

The MOH, which was informed of the error on July 13, said the mislabelled positive sample belongs to a migrant worker who had been isolated since his swab, and had not been in contact with anyone else.

He has since been admitted to the National Centre for Infectious Diseases and remains in a stable condition.

Meanwhile, all 71 students and staff members who were the close contacts of the first case at Jurong West Secondary School have also tested negative.

TTSH said of the error: "We are sorry for the mistake and sincerely regret the inconvenience caused to our patients and her school."

"We audited our laboratory testing for Covid-19 for that period and no other mislabelling was discovered.

"We have also put in place additional checks to prevent such an incident from occurring again," it added.

Meanwhile, Sec 1 students at Jurong West Secondary School will continue home-based learning until Friday, as a number of teachers from the school are still serving home quarantine orders, said Ms Liew.

Classes for all other levels will continue in school as per normal.

Ms Liew said that all schools have implemented comprehensive safe management measures to ensure the safety of students and staff, and minimise the risk of transmission.

This includes spaced-out seating in classrooms to ensure safe distancing, the wearing of face masks, staggered arrival, dismissal and recess timings, and minimising intermingling across classes and levels.

"Students should also head directly home after school," said Ms Liew.

"It is also equally important that each of us exercises personal responsibility.

"We would like to remind all parents, staff and students that if a student or any adult family member is unwell, the student should not go to school."

Education Minister Ong Ye Kung said on Facebook yesterday: "On July 10, all of us at MOE were dismayed when we learnt that at Jurong West Secondary School, a student who caught the Covid-19 virus at home has infected another classmate.

"This would have been our first recorded Covid-19 infection in school, despite all our precautionary measures."

He added: "To our relief, TTSH and MOH have clarified that it was a case of erroneous reporting by the testing laboratory."