From the TTC website at this link.
Antimicrobial Surface Treatment
"The interior surfaces (of subway cars) are treated with Bombardier’s Antimicrobial Surface Treatment Program. This proven technology helps create a healthier and safer environment for commuters, travelers and employees as it prevents the spread of influenza and other viruses, as well as moulds that deteriorate vehicles and transit facilities."
Assuming by "viruses", that it includes COVID-19.
The anti-microbial coating on stanchions is used on the new streetcars, as well.