effect of tetanus‑diphtheria vaccine on immune response to hepatitis b vaccine in low‑responder individuals

background: conventional hepatitis b virus (hbv) vaccination fails to achieve efficient protection in about 5–10% of the world population. hence, different strategies have been adopted to ameliorate hbv antibody titers. this study aimed to evaluate the concurrent application of tetanus‑diphtheria (td) and hbv vaccination on hepatitis b surface (hbs) antibody titer in low‑responder healthy individuals. methods: this was a randomized clinical trial, which was implemented among 140 of medical staff working as health‑care workers assumed as low‑responders. the subjects were randomly allocated to either control or interventional groups. the control and interventional groups received hbv recombinant vaccine while the latter group was also vaccinated through td. enzyme‑linked immunosorbent assay was applied to measure hbs antibody (hbsab) titers just before and 6 months after the last vaccination. all data were entered into spss software. independent t‑test, paired t‑test, and chi‑square or fisher’s exact test were applied for data comparison. results: antibody titers of the subjects in the intervention and control groups soared from 49.08 ± 20.08 iu/l to 917.78 ± 204.80 iu/l and from 46.95 ± 18.55 to 586.81 ± 351.77 iu/l, respectively (both p < 0.001); nevertheless, by comparison with control group, variation of antibody titer in the interventional group was significantly higher (p <0.001). conclusions: concurrent application of td and hbv vaccine could effectively enhance protective levels of hbsab titers in low‑responder individuals.