COVID-19 vaccination drive is poised to shift into high gear this week as the federal public health agency prepares to take delivery of the largest number of doses since the launch of the immunization effort.Nearly 1.2 million doses of the Pfizer-BioNTech vaccine are set to arrive this week, alongside 846,000 shots of the product developed by Moderna.Figures from the Public Health Agency of Canada suggest the pace set over the next seven days will mark the start of a sustained delivery ramp-up, with Pfizer-BioNTech expected to continue providing weekly shipments of at least a million doses for the foreseeable future.