Canadian provinces suspended use of the Oxford-AstraZeneca COVID-19 vaccine in people under age 55 on Monday, acting on an advisory committee’s concerns about a possible link between the shot and rare blood clots. Meanwhile, British Columbia imposed new public-health measures for the next three weeks to slow the rapid spread of the virus, as it announced 2,518 new cases over the past three days. Dr. Shelley Deeks, the vice-chair of Canada’s National Advisory Committee on Immunization, said the committee updated its recommendations amid new data from Europe that suggests the risk of blood clots is now potentially up to one in 100,000—much higher than the one in one million risk believed before. Health Canada demanded Monday that AstraZeneca do a detailed study on the risks and benefits of its COVID-19 vaccine across multiple age groups, and Deeks said the advisory committee recommended the shot be suspended for younger groups pending …