The Vaccines Vial Monitor (VVM) on a vaccine vial shows the inner square DARKER than the outer circle. What action should the healthcare worker take?

• A Use the vaccine immediately as it is at peak potency
• B Place it in a refrigerator and recheck after 24 hours
• C Use if VVM shows Stage 3 or later only
• D Discard the vaccine — it has been exposed to excessive heat and should NOT be used ✓

Explanation

A VVM with the inner square equal to or darker than the outer circle (Stage 3 or 4) indicates cumulative heat damage and the vaccine must be discarded. Only vaccines with the inner square lighter than the outer circle (Stage 1 or 2) should be used. This is the universal cold chain checkpoint before every vaccination.

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.