Evaluation of Cold Chain Maintenance for Vaccine Storage at Local Government Immunisation Stores in Borno State

Effective cold chain maintenance is critical to preserving vaccine potency from manufacture to point of administration. In Borno State, North East Nigeria, cold chain infrastructure has been severely disrupted by over a decade of humanitarian crisis, raising concerns about vaccine quality throughout the immunisation programme supply chain. This study evaluated cold chain maintenance practices at twelve local government immunisation stores in Maiduguri, Jere, and Konduga. Assessment included evaluation of cold chain equipment functionality, temperature monitoring records, stock management practices, vaccine vial monitor usage, and storage compliance against the National Expanded Programme on Immunisation guidelines. Temperature excursion events were identified by reviewing continuous temperature data from refrigerator log cards over a six-month period. Cold chain equipment was functional in only 58% of stores, with generator-dependent facilities experiencing frequent power interruption-related excursions. Temperature excursions below 2 degrees Celsius were recorded in four stores, with potential freeze damage to aluminium-salt adjuvanted vaccines. VVM indicators were used correctly in 67% of stores. Stock management practices including first-in-first-out application were poor in eight of twelve stores. These findings highlight urgent cold chain infrastructure and capacity gaps in Borno State LGA immunisation stores, with direct implications for vaccine quality and programme effectiveness. Keywords: cold chain, vaccine storage, immunisation, Borno State, temperature monitoring.