Influenza in Canada.
D000041:Absenteeism; D002170:Canada; D002318:Cardiovascular Diseases / Q000401:mortality; D005060:Europe; D006801:Humans; D007251:Influenza, Human / Q000453:epidemiology* / Q000401:mortality; D012140:Respiratory Tract Diseases / Q000401:mortality; D006113:United Kingdom; D014481:United States