Challenges and lessons learned during the switching of rotavirus vaccine from Rotarix to Rotavac in Zambia
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Published on: November 1, 2011
E M Mpabalwani1, C Sakala2, E Kamiji2
1University of Zambia, School of Medicine, Department of Paediatrics & Child Health, Lusaka, Zambia; University Teaching Hospitals, Children's Hospital, Lusaka, Zambia.
Insights
Rotavirus vaccine shortages in Zambia led to increased childhood diarrhea hospitalizations and a three-fold rise in infant mortality. Urgent improvements in vaccination documentation are needed to prevent future disruptions.
Area of Science:
- Pediatrics
- Vaccinology
- Public Health
Background:
- Zambia has monitored rotavirus diarrhea in children under five since 2007.
- A global rotavirus vaccine shortage in 2021-2022 left many Zambian children unvaccinated, increasing their risk of severe gastroenteritis.
Purpose of the Study:
- To evaluate the impact of rotavirus vaccine stock-outs and formulation changes in Zambia.
- To analyze trends in rotavirus vaccination coverage, hospitalizations, and mortality.
Main Methods:
- A desk review examined children under five (2017-2023) and national vaccine coverage data (2014-2023).
- The Rotarix vaccine stock-out period was defined as March 2022 to April 2023.
- Hospitalization data, clinical information, and rotavirus ELISA results were analyzed.
Main Results:
- Despite increased vaccination numbers, 2.63 million children missed vaccination between 2016-2023.
- Diarrhea hospitalizations and rotavirus positivity rates remained stable during vaccine stock-outs.
- Infant mortality rates tripled during the rotavirus vaccine stock-out period.
Conclusions:
- Global supply chain issues reversed progress in rotavirus disease control, causing missed vaccinations and increased mortality.
- The COVID-19 pandemic likely exacerbated vaccination disruptions.
- Updating vaccination cards is crucial for effective rotavirus vaccine management.
Introduction:
Active Rotavirus diarrhea surveillance has been ongoing in Zambia at three dedicated sentinel sites since 2007, focusing on hospitalized children under five years of age. During 2021 and 2022, many African countries, including Zambia, experienced a severe shortage of rotavirus vaccines. This vaccine shortage resulted in many children who were eligible for vaccination remaining unvaccinated. Consequently, these children were exposed to a higher risk of severe acute gastroenteritis.
Methods:
To ascertain the impact of rotavirus vaccine stock-out and switch in Zambia, a comprehensive desk review was conducted focusing on the switch of the vaccine from Rotarix to Rotavac and the change of the Rotavac formulation. This review encompassed all children under five years of age recruited at the surveillance sites between 2017 and 2023 and the country's comparison of national administrative and WUENIC 2023 rotavirus vaccine coverage rate estimates for 2014 to 2023. March 2022 to April 2023 was defined as the Rotarix vaccine stock-out period. Hospitalization trends, demographic and clinical data, and rotavirus confirmed ELISA results were analyzed.
Results:
Following the introduction of rotavirus vaccine, the number of fully vaccinated children increased steadily over the years, reaching 4.73 million in 2023. However, 2.63 million children missed vaccination between 2016 and 2023. The administrative and WUENIC 2023 estimates for rotavirus coverage rates were the same during the period under review. Hospitalized diarrhea cases and rotavirus positivity rates remained essentially the same during the in-stock and stock-out periods of rotavirus vaccine. However, mortality rates increased three-fold during the vaccine stock-out period.
Conclusion:
The impact of the Rotarix vaccine era was reversed due to the global supply chain disruptions, leading to missed vaccinations, increased diarrhea-related hospitalizations, and higher infant mortality in Zambia. The COVID-19 pandemic may also have further disrupted the vaccination sessions, further impacting rotavirus vaccination. Rotarix shortages likely contributed to rising rotavirus cases. There is an urgent need to completely replace the old under-5 vaccination card with a revised one to improve documentation for new rotavirus vaccines.
