During a routine audit of a peripheral health centre's ice-lined refrigerator, the cold chain handler is asked which vaccine must NEVER be exposed to freezing temperatures. Which of the following is correct?
- A BCG
- B Measles/MR
- C Hepatitis B ✓
- D Oral polio vaccine
Correct answer: C. Hepatitis B
Explanation
Hepatitis B vaccine, along with DPT, pentavalent, IPV, TT and PCV, is freeze sensitive and loses potency irreversibly if frozen, so it is stored in the body of the ILR away from the freezer wall. BCG, measles/MR and OPV are heat sensitive rather than freeze sensitive and tolerate freezing, which makes them the classic wrong answers in cold chain questions.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.