“…This is most likely due to a high number of patients having detectable antibodies pre-vaccination, reflecting previous use of influenza vaccine in our patient cohort [30,34,35]. After taking into consideration the pre-vaccination titers [28], seroconversion rates increased up to 32-38% for influenza A strains, a rate near of the 40% seroconversion rate which is considered as appropriate for the general population [9,36].…”