After receiving the DTaP vaccine, what symptom should a parent expect as a normal occurrence?

After receiving the DTaP vaccine, it is common for children to experience redness at the injection site. This symptom is a typical local reaction to the vaccine, as the body responds to the antigen introduced through the injection. The redness indicates inflammation, which is a natural response of the immune system as it begins to recognize and build immunity against the diphtheria, tetanus, and pertussis bacteria.

Local reactions such as redness, swelling, or tenderness at the injection site are expected and usually resolve quickly without any need for further medical intervention. This response is a sign that the body is developing the appropriate response to the vaccine.

In contrast, the other symptoms mentioned may warrant further attention. Severe fatigue lasting longer than 24 hours, continuous crying for more than 3 hours, and a high fever exceeding 102°F can indicate more serious reactions that may require parental concern or consultation with a healthcare provider. These symptoms are not considered routine side effects of the DTaP vaccine and are less common following immunization.