**Question:** All of the following statements are true about DPT vaccine EXCEPT:

A. DPT vaccine is a combined vaccine that protects against diphtheria, pertussis (whooping cough), and tetanus.
B. DPT vaccine is given in a specific age-based schedule to ensure proper immune response.
C. DPT vaccine causes immediate symptoms like fever, redness, and swelling at the injection site.
D. DPT vaccine is contraindicated in patients with severe allergies to any of the vaccine components.

**Correct Answer: C. DPT vaccine causes immediate symptoms like fever, redness, and swelling at the injection site.**

**Core Concept:** DPT vaccine (Diphtheria, Pertussis, and Tetanus) is a combined vaccine used to protect against these three serious bacterial infections. The vaccine is given in a specific schedule to ensure optimal immune response and development of immunity.

**Why the Correct Answer is Right:** The correct answer (option C) highlights a common side effect of the DPT vaccine, which is the occurrence of local reactions like fever, redness, and swelling at the injection site immediately after administration. These reactions are a result of the body's immune response to the vaccine antigens and are normal reactions.

**Why Each Wrong Option is Incorrect:**

**A. False:** DPT vaccine is a combined vaccine, which means it protects against more than one disease. It protects against diphtheria, pertussis (whooping cough), and tetanus. This option misleadingly suggests that it is only protecting against one disease, which is incorrect.

**B. True:** DPT vaccine is given following a specific schedule to ensure an optimal immune response and development of immunity. Vaccine schedules are designed to ensure adequate time for the body to mount a proper immune response, which is crucial for vaccine efficacy.

**D. True:** DPT vaccine is contraindicated (not recommended) in patients with severe allergies to any of the vaccine components. This option is correct as it highlights a potential contraindication to administering the vaccine.

**Clinical Pearl:**

DPT vaccine is considered a safe and effective tool for preventing diphtheria, pertussis, and tetanus infections. However, it is crucial to assess the patient's medical history and specifically check for severe allergies to any of the vaccine components before administering the vaccine. This ensures patient safety and prevents potential allergic reactions. Understanding contraindications is important for practicing safe medicine and making informed clinical decisions.