Ontario students will require negative COVID test in order to return to school only if they have either fever, cough, loss of taste or smell, or shortness of breathe. Runny nose or sore throat no longer require testing but home monitoring for 24 hours.

Medical Mythbusting Commentary for October 2, 2020

Source:
Students with just a runny nose or a sore throat will now be allowed to return to school after 24 hours

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