Relationship of influenza vaccine match and use rate to medically attended acute respiratory illnesses in older residents of Maryland. November 13, 2012

► Retrospective CDC data revealed that influenza vaccine match to circulating influenza viruses varied from 2001 to 2008. ► Increased influenza vaccine match and use were associated with decreased respiratory illness. ► Increased proportions of A/H3N2 viruses were associated with higher rates of respiratory illness.