Which vaccination schedule includes a DTaP booster at age 4-6 years?

The childhood immunization schedule is the correct answer because it outlines the vaccinations that are recommended for infants, children, and adolescents, including the DTaP (diphtheria, tetanus, and pertussis) vaccine. The specific booster for DTaP is given at the age of 4 to 6 years as part of the routine immunizations to ensure continued protection against these diseases as the child grows.

This booster is important in maintaining immunity since the initial doses are given in infancy and early childhood. By providing this booster at the appropriate age, the schedule aligns with the developmental needs of children and the epidemiology of these infections in the population.

In contrast, the other vaccination schedules mentioned do not include a DTaP booster for this age group. The adult immunization schedule focuses on vaccines required for adults, the travel vaccination schedule is tailored for vaccines necessary for international travel, and the seasonal flu vaccination schedule pertains specifically to influenza vaccinations. None of these schedules address the specific needs for DTaP boosters in early childhood.