COVID-19 cases appear to be on the rise again in Ontario, and business groups are calling for a vaccine certificate system as a means to avoid another lockdown.Ontario has reported rising positivity rates and more than 300 new COVID-19 cases for the past four days, with more than 400 on Sunday – levels not seen since mid-June.Premier Doug Ford has rebuffed calls from medical, political and business groups to implement a vaccine certificate system for non-essential activities, saying he doesn’t want a “split society.”But while saying he “can’t stand lockdowns,” he also has not ruled out having to enact another one.