Student misdiagnosed with Covid-19 due to human error in lab
TTSH lab mislabelled her sample, which belonged to a migrant worker
A student from Jurong West Secondary School was wrongly diagnosed with Covid-19 as a result of a hospital's mislabelling of testing samples.
The Secondary 1 female student was reported last Friday to have tested positive for the coronavirus.
She was swabbed as she had been in contact with a schoolmate, a 13-year-old boy, who was previously confirmed to be infected. The boy had been linked to a household infection and his case was announced on July 7.
The school then placed all its Sec 1 students on home-based learning (HBL) from July 8 and 9.
Upon learning of the "second case", it extended HBL to this Friday as an added precaution.
But in a Facebook post yesterday, Tan Tock Seng Hospital (TTSH) said there had been erroneous reporting of the female student's case from its laboratory, which had administered the original test.
"This arose from a human error in the laboratory where two patients had their specimens cross-labelled," TTSH added.
Two subsequent tests at the National University Hospital, where the female student, known as Case 45655, was admitted, turned out negative both times.
TTSH said its laboratory then repeated a polymerase chain reaction test on the original sample and found the result to be negative.
The mislabelled positive sample was found to belong to a migrant worker.
The Ministry of Health (MOH) was informed of the error on July 13.
The migrant worker has been isolated since his swab and had not been in contact with anyone else. TTSH said he has been admitted to the National Centre for Infectious Diseases and remains in stable condition.
Both patients have been informed about the mislabelling, and the female student, who is well, has been discharged.
TTSH apologised for the error and said: "We have audited our laboratory testing for Covid-19 for that period and no other mislabelling was discovered."
It added that additional checks have been put in place to prevent such an incident from occurring again.
MOH said it takes a serious view of the error and is investigating the matter.
Minister for Education Ong Ye Kung said on Facebook yesterday that the ministry was dismayed when it learnt the female student had "caught" the virus from a classmate.
He said: "This would have been our first recorded Covid-19 infection in school, despite all our precautionary measures. To our relief, TTSH and MOH have clarified that it was a case of erroneous reporting by the testing laboratory."
Ms Shirley Wee, 56, whose son is a Sec 4 student at the school, was concerned when she heard about the "second case" at the school.
She said: "But I was not too worried because the students were put on HBL and the school had been disinfected.
"I am relieved this has been cleared up so we now know there is no student-to-student transmission."