COVID-19 vaccination campaigns in fragile and conflict-affected settings, Somalia.

Problem: By 31 December 2021, only 5.5% (861 879/15 670 530) of the Somali population had been fully vaccinated against coronavirus disease 2019 (COVID-19). Approach: To rapidly increase COVID-19 vaccine coverage in 2022, the health ministry and its partners (World Health Organization and United Nations Children's Fund) adopted a more responsive strategy. This strategy included careful microplanning, better targeting of populations and providing people-centred vaccination services close to their homes. These services were combined with childhood vaccination and basic health-care provision using the existing polio network and community health workers. Additionally, a digital tool for recording COVID-19 vaccination data and a mobile phone-based electronic registration system were introduced. Local setting: Somalia, a fragile and conflict-affected state, faced challenges when implementing COVID-19 vaccination, including inexperience in managing mass adult vaccination, inadequate infrastructure and health workforce. Furthermore, insecurity in some areas and severe drought resulted in large-scale displacement of people. Relevant changes: The implementation of a more context-specific strategy helped Somalia reach substantially more people with COVID-19 vaccination and 42.1% coverage by 31 December 2022. Additionally, 84 600 zero-dose children received their first childhood vaccine during the integrated campaigns. The increased coverage has led to public health benefits that outweigh the investment in the COVID-19 vaccination campaigns. Lessons learnt: Successful roll-out of adult vaccination is achievable even in a fragile and conflict-affected setting through implementation of a tailored contextualized approach. Key factors include good microplanning, use of digital tools, better population-targeting, bundling vaccines together and delivering vaccination services close to people's homes.

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.