Ontario Health, which has set up laboratories across the province for testing, acknowledged the error in a statement to Global News.
“Hospital laboratories have been collaborating to shoulder the workload around the large volume of testing required,” the statement read.
“In some cases, laboratories conducting testing for other hospitals/assessment centres have asked those sites to notify the public health unit of positive results so the public health units can begin contact tracing.
“In this case, there was a breakdown in communication and a number of positive tests were not communicated to the public health units.”
Ontario Health said they take “full responsibility.”
As first reported by the CBC, the reporting failures involved the William Osler Health System and Mount Sinai Hospital.
Initial reports indicated around 700 tests went unreported, but officials said Tuesday that approximately 485 people were affected.
“The focus is now ensuring that people with positive tests were contacted and that public health agencies know who they must involve in case management and contact tracing,” Ontario Health said.
“Calls to patients to date have confirmed that the majority of patients knew that they had had a positive test. This is because people can go online to see their results and/or they’ve been contacted by a physician responsible for suggesting they be tested.”
However, officials said “many” of the affected patients will require contact tracing that wasn’t previously conducted.
“Ontario Health is very sorry that this has occurred. The impact of the error may not be fully understood for some time,” the statement said.
Ontario Health said once public health agencies complete contact tracing, there will be a better understanding of the impact of the reporting failures.
Epidemiologist Raywat Deonandan said the failure to report the hundreds of positive cases may be directly tied to recent spikes reported in Ontario.
On Tuesday, the province reported 446 new COVID-19 cases — the highest increase since May 24.
“I suspect that a lot of the spike in cases that we’re seeing now are due to the spread of unidentified contacts of these initial cases,” Deonandan said.
— With files from Morganne Campbell
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