Facility Level Cold-Chain Maintenance, Temperature-Monitoring and Stability of Live Attenuated Vaccines in Kisumu County, Western Kenya

Abstract

Background: Challenge of live-attenuated vaccines instability in Kenya Expanded Program on Immunization still persists in varying degrees. It potentially affects their safety and clinical performance. Experiences of occasional resurgence of diseases preventable by these vaccines in Kisumu County were suspected to be associated with lapses in cold-chain system at health facility levels. The study assessed cold-chain equipment at facility level to determine specific lapses and their influence on stability of live-attenuated vaccines in Kisumu.

Method:  Using a cross-sectional design with repeated analytical observations, site level data was collected in three cycles from a stratified sample of 120 out of 170 health facilities between October 2018 and March 2019. A pretested check list was used. Through SPSS data were summarized descriptively for both dependent and independent variables. Regression with a binomial link performed. Chi-square, Confidence-intervals and odds ratios reported.

Result: Statuses of cold-boxes and vaccines carriers were satisfactory. Of 120 fridges, 60% were functional; 34.2% partially; 5.8% non-functional; 28.3% expired while 45% had no sustainable power supply. Private facilities had four of seven non-functional fridges, all being below WHO recommendations. Public facilities were more likely to have stable OPV (95%C. I 1.4 – 6.7, OR 3.0, p-value 0.006) and measles-rubella (95% C.I 1.2 – 5.5, OR 2.5, p-value 0.019). Fridges on electric grid without backup were less efficient in maintaining stability of measles-rubella vaccines as compared to fridges on solar (95%C, I 0.05 - 0.9, OR 0.2, p-value 0.0042). Efficiently functional fridges on EG power source with backups significantly increased the likelihood of stable measles-rubella vaccines (95%C. I 2.4 -187.4 OR 21, p-value 0.006). An expired fridge was less likely to keep stable OPV (95% C.I 2 – 11, OR 4.7, p-value <0.001) and measles-rubella vaccines (95%C. I 3.1 -18.7, OR 7.1, p-value <0.001). BCG vaccines were unaffected.

Conclusion:  Cold-chain management lapses on fridges and occasional erratic power supply, higher at private facilities, significantly destabilize OPV; measles-rubella and ROTA vaccines, so probably associated with upsurges of measles and Rota illnesses. This calls for scrupulous adherence to cold-chain policies specifying scheduled supply / replacement of fridges with power back-up options or solar for sustainability and temperature control.