Intradermal and virosomal influenza vaccines for preventing influenza hospitalization in the elderly during the 2011-2012 influenza season: A comparative effectiveness study using the Valencia health care information system

During the 2011-2012 influenza season the risk of hospitalization for influenza was reduced by 33% in non-institutionalized elderly adults who were vaccinated with intradermal-TIV compared with virosomal-TIV.