UPDATED: Public health units not told about roughly 700 positive COVID-19 cases


We are learning that hundreds of COVID-19 cases were not reported to public health units because of a mix up involving William Osler Health System.

The exact number is unclear but CBC News reports roughly 700 positive tests were missed, which means those patients contacts were not traced for weeks.

The tests were conducted by William Osler, which runs hospitals in Etobicoke and Brampton and a drive-thru COVID-19 assessment centre. They were processed in the lab at Mount Sinai.

Staff at each hospital reportedly thought it was up to the other hospital to inform public health.

The missed tests go as far back as April but public health units only learned about them recently. Most cases were in Toronto, Peel and York Region.

Ontario Health is the agency responsible for COVID-19 labs.

In a statement to CTV News Toronto they say, "The provincial network has confirmed with all laboratories that there is a clear and documented understanding of who is informing local public health units to ensure timely case investigation and contact tracing."

CBC reports, that according to provincial officials, it was up to William Osler to inform public health.

NEWSTALK 1010 reached out to Ontario Health and Health Minister Christine Elliott's office early Tuesday morning. As of 9 a.m. there had been no response.


Ontario Health provided the following statement to NEWSTALK 1010 on Tuesday afternoon:

"Ontario Health has set up a system of laboratories across the Province of Ontario in three months.  This is a major accomplishment at a time of extreme pressure due to COVID-19 and the need to test for the virus.

Hospital laboratories have been collaborating to shoulder the workload around the large volume of testing required. 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 takes full responsibility.  The assessment centre and the COVID-19 lab are doing excellent work.

The provincial lab network has now confirmed all laboratories doing COVID-19 testing are clear on who contacts the patients and who contacts the public health agencies, to ensure timely case investigation and contact tracing going forward.

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.

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, many of these patients still require case management by public health, which is being rectified by the public health units.

As the work continues to understand the list of positive cases, it has been determined that approximately 485 people are involved.

Ontario Health is very sorry that this has occurred.  The impact of the error may not be fully understood for some time.  When public health agencies complete their case management and contact tracing there will be a greater understanding of the impact."