Canada's latest COVID-19 surge is being fuelled by the BA.5 variant. It's prompting some public health officials to make fourth jabs of a COVID-19 vaccine available to all adults. While most provinces are already offering fourth doses to their most vulnerable residents, some — such as New Brunswick, Quebec and P.E.I. — are urging the general adult population to sign up as well. However experts are divided about the urgency at which Canadians should receive a second boost, and when. Prof. Raywat Deonandan is an epidemiologist specializing in global health at the University of Ottawa. He breaks down what we need to know about the future of COVID-19 vaccination.