Study protocol for temperature monitoring in the vaccine cold chain

Overview

Improperly maintained or outdated refrigeration equipment, poor compliance with cold-chain procedures, inadequate monitoring and poor understanding of the dangers of vaccine freezing contribute to the weakness of the existing cold chain.

Emphasis has long been placed on keeping vaccines cold, with less attention devoted to preventing vaccine damage by freezing. Published reports and field evidence demonstrate that freezing of vaccines in the cold chain is commonplace, potentially resulting in the widespread delivery of vaccines whose potency has been compromised by the disassociation of antigen from the adjuvant.

In response to this danger, WHO guidelines clearly state that adjuvant vaccines must not be exposed to freezing temperatures. This Protocol is designed to:

1) document temperature exposures throughout the vaccine cold chain with a special emphasis on the level of freezing; and

2) identify specific problem areas where corrective actions are warranted.