A frontline TTC worker has tested positive for COVID-19, marking the second employee of Toronto's transit agency to catch coronavirus in the last week. 

According to public transit worker union ATU Local 113, the TTC employee is a subway operator at the Wilson division. 

They tested positive for COVID-19 today, but haven't been at work since the morning of Monday, March 16. 

"... the member left work shortly after their shift began at 5:30 p.m. because they felt unwell," said ATU Local 113. "Again, the member has been home since that time." 

ATU Local 113 has learned on March 24 that a TTC Subway operator has tested positive for the coronavirus (COVID-19). While the case is still under investigation, we wanted to update members as soon as possible.

Please click the link for more info.https://t.co/N9q38kqLQZ

— ATU Local 113 (@ATUlocal113) March 24, 2020

It's unclear how many TTC employees will be forced into self-isolation following the diagnosis, which was announced this evening. 

"ATU Local 113 is working with the TTC and Toronto Public Health to determine next steps/actions to further protect the health of workers and riders. More details to come." 

Last week saw up to 170 employees sent into self-isolation after a mechanic at the TTC's bus maintenance facility at Bathurst and Davenport tested positive for COVID-19. 

The case comes shortly after the TTC allowed bus drivers to wear face masks, and implemented new rules for bus passengers to enforce social distancing, including using rear doors only, and discontinuing the use of transfers completely.