Randomized, controlled trial of high-dose influenza vaccine among frail residents of long-term care facilities.

Background: Despite vaccination, residents of long-term-care facilities (LTCFs) remain at high risk of influenza-related morbidity and mortality. More-effective vaccine options for this population are needed.

Methods: We conducted a single-blinded, randomized, controlled trial comparing high-dose (HD) to standard-dose (SD) inactivated influenza vaccine (IIV) in 205 frail, elderly residents of LTCFs during the 2011-2012 and 2012-2013 influenza seasons.