Final answer:
The DTaP vaccine can be given to children starting at 2 months of age, while the Td vaccine is recommended for adolescents and adults.
Step-by-step explanation:
The earliest age at which tetanus and diphtheria vaccinations can be given depends on the specific vaccine being used. According to the CDC recommendations, children can receive doses of the DTaP vaccine at 2, 4, 6, and 15-18 months of age, and another at 4-6 years of age. For adolescents and adults, one dose of the Td vaccine is recommended as a tetanus booster every 10 years.