The DTaP vaccine protects your child from getting tetanus (lockjaw), diphtheria, and acellular pertussis (whooping cough). All three of these are potentially life-threatening bacterial infections.
The bacteria the causes tetanus is called Clostridium tetani and is often found in the soil. In the United States, tetanus is most often transmitted through a break in the skin, such as a deep puncture, like stepping on a nail. However, injuries that involve dead skin (burns, frostbite, gangrene, crush injuries, etc.) are more likely to cause tetanus. Wounds contaminated with soil, saliva, or feces, and that are not properly cleaned, as well as punctures with non sterile needles are at an increased risk for tetanus.