Immunogenicity and safety of a trivalent tetanus, low dose diphtheria, inactivated poliomyelitis booster compared with a standard tetanus, low dose diphtheria booster at six to nine years of age. Munich Vaccine Study Group.

OBJECTIVE

To compare the immunogenicity and safety of a trivalent tetanus-diphtheria (low toxoid content)-inactivated poliomyelitis vaccine, Td-IPV (Revaxis; Pasteur Merièux), with a tetanus-diphtheria (low toxoid content) vaccine, Td (Td-Impfstoff Mérieux; Pasteur Merièux), when administered as a booster to children age 6 to 9 years.

METHODS

A group of 301 children were randomized and vaccinated with Td-IPV (n = 150) or Td (n = 151) in this open, controlled, multicenter trial. Serum specimens were obtained before and 28 days after vaccination. Safety was assessed for up to 28 days postvaccination by parental diary cards. Solicited local and systemic reactions were recorded for 7 days after vaccination.

RESULTS

Seroprotection (enzyme-linked immunosorbent assay titer, > or =0.10 IU/ml) against tetanus and diphtheria was induced by either Td-IPV or Td in all subjects. Tetanus and diphtheria geometric mean titer were higher after Td (34.0 and 5.74 IU/ml) than after Td-IPV (15.9 and 4.38 IU/ml). All subjects boosted with Td-IPV were seroprotected against each type of poliovirus (neutralizing antibody titer, > or =5/dilution). The most frequently reported solicited local and systemic symptoms were pain triggered by movement of the arm (54% vs. 39.1%) and headache (17.3% vs. 7.3%), after Td-IPV and Td, respectively. All other events were similar between the two groups. Reactions were generally mild and all were temporary.

CONCLUSIONS

A booster dose of Td-IPV induced in all children seroprotection against tetanus, diphtheria and poliomyelitis. The overall safety profile of the two vaccines was acceptable.