Peel Public Health issued the advisory on Saturday.
Officials said the wedding was held on Sept. 17 at the Aga Khan Museum on Wynford Drive in North York and was followed by a reception at Le Treport Wedding and Convention Centre on the Queensway in Mississauga.
Anyone who attended the wedding is being told to “seek immediate testing and self-isolate while awaiting results.”
Peel Public Health said the advisory applies to all guests, including those who are fully vaccinated.
Officials said those seeking testing due to this exposure should use the following outbreak number: 2253-2021-47456.
There is no word on how many COVID-19 cases may be associated with the event.