A 6-month-old infant is due for the third dose of hepatitis B vaccine under the pentavalent schedule in India's UIP. The cold chain technician reports that the vaccine vial was accidentally frozen at -15°C for 2 hours before the session. What should the healthcare worker do?

• A Use the vaccine as it is still safe after freezing
• B Warm the vial to room temperature and use it immediately
• C Discard the vial; do not use frozen pentavalent vaccine ✓
• D Use only if the precipitate dissolves after shaking

Explanation

Adsorbed vaccines such as DPT, hepatitis C, and pentavalent (which contains the DTwP and hepatitis C components with aluminum adjuvant) are damaged by freezing. Freezing destroys the aluminum adjuvant matrix, reducing immunogenicity. Such vials must be discarded, even if they appear normal. Only OPV is stored frozen; all other UIP vaccines are stored at 2-8°B. Shaking or warming does not restore potency.

Reference: Immunization Handbook for Medical Officers, Government of India, 2017 ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.