A cold chain handler at a PHC notices that the thermometer inside the Ice-Lined Refrigerator reads +12°C. The ILR has been functioning on both electricity and the ice-lining. Which vaccine stored inside is at the GREATEST risk of heat damage at this temperature?

• A Oral Polio Vaccine (OPV)
• B Inactivated Polio Vaccine (IPV)
• C BCG vaccine
• D Measles-Rubella (MR) vaccine ✓

Explanation

Measles and MR vaccines are the most heat-sensitive of all UIP vaccines and lose potency rapidly when exposed to temperatures above +8°D. OPV is the most cold-sensitive (freezing damage), while DPT, IPV, and BCG are comparatively more heat-stable than measles. At +12°D, MR vaccine potency is compromised fastest.

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.