Inclusion Criteria :

• Healthy, as determined by medical history and physical examination.
• Aged 4 to 6 (< 7) years at the time of study vaccination on Day 0.
• Signed and dated informed consent form that has been approved by the Institutional Review Board (IRB) by the parent or legally authorized representative.
• Signed and dated informed assent form from the subject if required by the IRB.
• Able to attend scheduled visits at Visit 1 and Visit 2 and able to comply with all trial procedures. Subjects will be invited to participate in the long-term immunogenicity follow-up study but a commitment to participate in the long-term is not required as an inclusion criterion.
• Documented vaccination history of 4 previous doses of DAPTACEL according to the recommended national immunization schedule for DTaP.

Exclusion Criteria :

• Participation in another clinical trial in the 4 weeks preceding the trial vaccination.
• Planned participation in another clinical trial during the original trial period.
• Congenital or acquired immunodeficiency, immunosuppressive therapy such as anti-cancer chemotherapy or radiation therapy within the preceding 6 months, or long-term systemic corticosteroids therapy.
• Systemic hypersensitivity to any of the vaccine components or history of life-threatening reaction to the trial vaccine or a vaccine containing the same substances.
• Chronic illness at a stage that could interfere with trial conduct or completion.
• Blood or blood-derived products received in the past 3 months.
• Receipt of any other vaccine within 30 days prior to study vaccination, or planning to receive another vaccine within 30 days before the Visit 2 blood draw (with the exception of the annual influenza vaccine).
• History of diphtheria, tetanus or pertussis infection (confirmed either serologically or microbiologically).
• Thrombocytopenia or bleeding disorder contraindicating IM vaccination.