Regarding the pentavalent vaccine (DPT-HepB-Hib) used in India's Universal Immunization Programme, which component is responsible for the highest rate of local adverse reactions at the injection site?
- A Whole-cell pertussis component ✓
- B Diphtheria toxoid
- C Hepatitis B surface antigen
- D Haemophilus influenzae type b conjugate
Correct answer: A. Whole-cell pertussis component
Explanation
The whole-cell pertussis component in DTwP-containing pentavalent vaccine is responsible for the highest rate of local adverse reactions including pain, swelling, redness, and induration at the injection site. This is a well-characterized reactogenicity profile of whole-cell pertussis vaccines compared to acellular pertussis vaccines. The diphtheria toxoid and Hib conjugate are relatively less reactogenic. Hepatitis A component rarely causes significant local reactions. This knowledge is important for counseling parents about expected post-vaccination reactions.
Reference: Plotkin's Vaccines, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.