Working notice and COVID-19

We are a BC employer. We have given an employee 3 weeks working notice prior to the COVID-19 virus becoming a huge topic. Now the employee has called in sick with mild but possible COVID-19 symptoms. As a precaution we are going to direct the employee to stay home for 14 days or until symptoms have completely disappeared. How does this affect their notice period – Do they technically have to be able to work their working notice period?