Vaccination strategies to identify and reach zero-dose and under-immunized children in crisis-affected states in Sudan: a qualitative study.

Abstract

Background: Globally, 21 million children were un- or under-vaccinated with Diphtheria-Tetanus-Pertussis (DTP)-containing vaccines in 2023. Around 20% of zero-dose children, those who had not received any DTP doses, live in conflict-affected settings in low and middle-income countries. There is insufficient evidence on vaccination interventions to identify and reach zero-dose children in these settings. This study aimed to map and assess current vaccination strategies to identify and reach zero-dose and under-vaccinated children in the crisis-affected states of South Kordofan, South Darfur and Blue Nile in Sudan.

Methods: We conducted a cross-sectional qualitative study guided by the (Identify-Reach-Monitor-Measure-Advocate (IRMMA) framework, developed by Gavi, the Vaccine Alliance. We conducted 20 individual semi-structured interviews during November and December 2022. We interviewed governmental and non-governmental vaccination stakeholders at federal, state and locality levels. We used the IRMMA framework to analyze the interview transcripts.

Results: Zero-dose and under-immunized children in the study sites were concentrated in opposition-controlled areas, nomadic communities, and remote rural areas. Zero-dose and under-immunized children in accessible areas were identified through routine vaccination strategies and surveillance reports. Various strategies were used in inaccessible areas. This includes tasking local institutions and individuals trusted by communities to identify and reach children, and infrequent integration and co-delivery of routine vaccines with other health interventions such as COVID-19 vaccination and insecticidal net distribution. There are inaccurate population estimates and a lack of guidance from ministries of health for measuring and monitoring zero-dose and under-immunized children. Respondents conflated advocacy with mobilization, and advocacy was broadly characterized as an ad hoc activity mostly connected to immunization campaigns.

Conclusions: Our study underscored the complexity of vaccinating zero-dose and under-immunized children in crisis-affected states of Sudan. Further research is needed to evaluate these practices and the role of non-governmental organizations (NGOs) and community engagement in improving vaccination coverage. Furthermore, exploring alternative funding methods and using geographic information systems (GIS) could enhance vaccination data and address funding limitations.