From CDC website, 04 February 2011
Each year, the Advisory Committee on Immunization Practices (ACIP) reviews the recommended adult immunization schedule to ensure that the schedule reflects current recommendations for the licensed vaccines. In October 2010, ACIP approved the adult immunization schedule for 2011, which includes several changes. The notation for influenza vaccination in the figure and footnotes was changed to reflect the expanded recommendation for annual influenza vaccination for all persons aged 6 months and older, which was approved by ACIP in February 2010. In October 2010, ACIP issued a permissive recommendation for use of tetanus, diphtheria, and acellular pertussis (Tdap) vaccine in adults aged 65 years and older, approved the recommendation that Tdap vaccine be administered regardless of how much time has elapsed since the most recent tetanus and diphtheria toxoids (Td)–containing vaccine, and approved a recommendation for a 2-dose series of meningococcal vaccine in adults with certain high-risk medical conditions. The vaccines listed in the figures have been reordered to keep all universally recommended vaccines together (e.g., influenza, Td/Tdap, varicella, human papillomavirus [HPV], and zoster vaccines). Clarifications were made to the footnotes for measles, mumps, and rubella (MMR) vaccination; HPV vaccine; revaccination with pneumococcal polysaccharide vaccine (PPSV), and Haemophilus influenza type b (Hib) vaccine. Finally, a statement has been added to the box at the bottom of the footnotes to clarify that a vaccine series does not need to be restarted, regardless of the time that has elapsed between doses.