Insufficient protection for healthy elderly adults by tetanus and TBE vaccines.

Abstract Little information is available on post-vaccination antibody concentrations and the duration of protection in persons of more than 20 years of age. We, therefore, measured antibodies specific for tetanus (TT) or tick-borne encephalitis (TBE) virus in 734 adults (age 18–93 years, 382 females and 352 males) and evaluated these data in connection with the time point of the last vaccination against tetanus or TBE and age. This analysis revealed that the time of the last vaccination as well as age had highly significant effects on tetanus and TBE titers ( p