Attenuated immune response to tetanus toxoid in young healthy men protected against tetanus

Tetanus booster is a routine procedure of tetanus prevention in populations with high risk of injury, independent of the levels of protection. But the immune response in already protected individuals is not well studied. We describe the kinetics of booster response in individuals by measuring tetanus antitoxin levels by indirect ELISA. A 6-month follow up was performed on 60 boosted individuals tested before, 1 week, 1, 2, 3 and 6 months after the booster. High initial protection (mean titer 1.08 IU/ml) and less than 3-fold increase after 1 month were observed. After 1 month of stable antitoxin levels, the levels slowly decreased and reached a mean titer of 1.78 IU/ml after 6 months. Individuals with initial levels