Lessons From the COVID-19 Pandemic Response Implementation: A Case Study of South Sudan and Sierra Leone.

INTRODUCTION: The COVID-19 pandemic caused havoc to health systems worldwide and in countries that already had weak health systems. There are lessons to be learned that could contribute to improved response preparedness to future public health emergencies, but there is little documentation on best practices in fragile countries. We describe lessons from South Sudan and Sierra Leone during the COVID-19 response implementation. METHODS: We conducted a retrospective descriptive analysis of COVID-19 vaccination implementation at national and subnational levels between 2020 and 2022 in South Sudan and Sierra Leone to identify those practices that had a positive impact on public health. RESULTS: Several interventions were identified that not only improved the COVID-19 situation but also had a positive effect on routine immunizations. The development of a near-real-time vaccination dashboard gave stakeholders a quick look at vaccine implementation, allowing them to make decisions based on current data. The experience acquired from deploying the COVID-19 dashboard has since been applied to the development of a routine immunization dashboard in South Sudan. Surge vaccination was an effective approach to improving COVID-19 vaccination uptake. A measles reactive campaign was conducted during the initial stages of the pandemic when movement was restricted; experience gained from that effort was subsequently applied to COVID-19 mass vaccination initiatives and outbreak reactive campaigns. Additional vaccinators recruited for COVID-19 response also received comprehensive Immunization in Practice training, allowing them to provide routine childhood vaccinations alongside COVID-19 vaccination, contributing to the maintenance of routine vaccination services in both countries. CONCLUSION: Lessons were learned during the COVID-19 response implementation that have had a positive impact on routine health services. However, it is essential that these effects are maintained and further refined to strengthen the country's preparedness for future public health emergencies and better support the broader immunization service delivery.

Estimating the Impact of Vaccination Campaigns on Measles Transmission in Somalia.

Somalia is a complex and fragile setting with a demonstrated potential for disruptive, high-burden measles outbreaks. In response, since 2018, Somalian authorities have partnered with UNICEF and the WHO to implement measles vaccination campaigns across the country. In this paper, we create a Somalia-specific model of measles transmission based on a comprehensive epidemiological dataset including case-based surveillance, vaccine registries, and serological surveys. We use this model to assess the impact of these campaign interventions on Somalian's measles susceptibility, showing, for example, that across the roughly 10 million doses delivered, 1 of every 5 immunized a susceptible child. Finally, we use the model to explore a counter-factual epidemiology without the 2019-2020 campaigns, and we estimate that those interventions prevented over 10,000 deaths.