In the Indian cold chain system, the deep freezer at district level maintains a temperature between minus 25 and minus 15 degrees Celsius. Which product is routinely stored in this equipment?

• A Oral polio vaccine ✓
• B Hepatitis B vaccine
• C Diluent for lyophilized vaccines
• D Pentavalent vaccine

Explanation

OPV is the only UIP vaccine that tolerates and requires freezing temperatures, so it occupies the deep freezer or the coldest basket of the ILR. Hepatitis A and pentavalent vaccines are adsorbed and freeze-sensitive: freezing causes adjuvant aggregation and loss of potency. Diluents must be cooled but never frozen, because freezing cracks glass ampoules.

Reference: Park's Textbook of Preventive and Social Medicine, 25th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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