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2. Statistics Canada, Canadian Community Health Survey (CCHS). CANSIM table 105-0502: Influenza immunization rate within last year. Available at ‘http://www5.statcan.gc.ca/cansim/a26.’ Accessed on 15 June 2013.
3. Influenza vaccination coverage - United States, 2000-2010;Setse;MMWR Surveill Summ,2011
4. Guidelines for prevention of nosocomial pneumonia. Prevention and control of pneumococcal disease;Centers for Disease Control and Prevention (CDC);MMWR Morb Mortal Wkly Rep,1997
5. Advisory Committee on Immunization Practices (ACIP) recommended immunization schedule for adults aged 19 years and older--United States, 2013;Bridges;MMWR Surveill Summ,2013