TORONTO—Canada on Monday suspended the use of the Oxford-AstraZeneca coronavirus vaccine for people under age 55 following concerns it might be linked to rare blood clots. The National Advisory Committee on Immunization had recommended the pause for safety reasons and the Canadian provinces, which administer health in the country, announced the suspension Monday. “There is substantial uncertainty about the benefit of providing AstraZeneca Covid-19 vaccines to adults under 55 given the potential risks,” said Dr. Shelley Deeks, vice chair of the National Advisory Committee on Immunization. Deeks said the updated recommendations come amid new data from Europe that suggests the risk of blood clots is now potentially as high as one in 100,000, much higher than the one in one million risk believed before. She said most of the patients in Europe who developed a rare blood clot after vaccination with AstraZeneca were women under age 55, and the fatality …