Benefits of Using Vaccines out of the Cold Chain: Delivering Meningitis A Vaccine in a Controlled Temperature Chain During the Mass Immunization Campaign in Benin

Background: In October 2012, the Meningococcal A conjugate vaccine MenAfriVac was granted a label variation to allow for its use in a controlled temperature chain (CTC), at temperatures of up to 40°C for not more than four days. This paper describes the first field use of MenAfriVac in a CTC during a campaign in Benin, December 2012, and assesses the feasibility and acceptability of the practice.

Methods: We implemented CTC in one selected district, Banikoara (target population of 147,207; 1-29 years of age), across 14 health facilities and 150 villages. We monitored the CTC practice using temperature indicators and daily monitoring sheets. At the end of the campaign we conducted a face-to-face survey to assess vaccinators' and supervisors' experience with CTC.

Findings: A mix of strategies were implemented in the field to maximize the benefits from CTC practice, depending on the distance from health centre to populations and the availability of a functioning refrigerator in the health centre. Coverage across Banikoara was 105.7%. Over the course of the campaign only nine out of approx. 15,000 vials were discarded due to surpassing the 4 day CTC limit and no vial was discarded because of exposure to a temperature higher than 40°C or due to the Vaccine Vial Monitor (VVM) reaching its endpoint. Overall confidence and perceived usefulness of the CTC approach were very high among vaccinators and supervisors.

Interpretation: Vaccinators and supervisors see clear benefits from the CTC approach in low income settings, especially in hard-to-reach areas or where cold chain is weak. Taking advantage of the flexibility offered by CTC opens the door for the implementation of new immunization strategies to ensure all those at risk are protected.