What a 1967 Gambia vaccine campaign shows about cold chains

Read WHO's 1967 Gambia example with cold-chain difficulty and health outcome as separate evidence.

8 December 2023Updated 23 September 2026

Short answer

State the country, programme, period, vaccine and transport system in any success account. Verify implementation with primary sources such as programme reports, field manuals and archival records; check temperature data, coverage and health-outcome claims separately. If evidence is unavailable, do not give outcome or loss figures; state the evidence gap.

WHO describes cold-chain difficulties for heat-sensitive measles vaccine in West and Central African campaigns. Measles transmission was interrupted in The Gambia by May 1967; that outcome cannot be attributed to one transport container.

Build an evidence file

Identify country or region, years, programme, vaccine and transport method. Verify implementation with the programme field manual and official report from that period; archival records may support equipment or route details.

Keep equipment use, monitoring/temperature records, and vaccination coverage or health outcomes in separate evidence tables. Sources may differ in measurement method, population and comparison period; do not collapse them into one outcome claim.

For lessons about current practice, separately check current vaccine product information and immunisation programme instructions. A historical transport account does not set current temperature, packing or product-release criteria.