Article de revue
“The opportunity to catch up”: from emergency response to immunization sustainability in Cameroon
The COVID-19 pandemic severely disrupted routine immunization globally and across Cameroon, causing a surge in “zero- dose” (ZD) children and exacerbating “missed opportunities for vaccination” (MOV). This necessitated accelerated recovery initiatives like the Big Catch-Up (BCU). This study explores BCU’s operationalization, implementation, and sustainability in Cameroon, assessing how vertical funding interacted with national health systems to reach ZD and under-immunized children. Focusing on four districts (urban, conflict-affected, isolated island, and remote rural), we triangulated data from 34 document reviews (e.g. national policies, operational plans, budget frameworks, and Expanded Program on Immunization reports), 37 key informant interviews across all health system levels, and 11 focus group discussions with 86 community stakeholders, including caregivers. Thematic analysis reveals that while BCU remained a campaign-style intervention with parallel reporting structures, its funding acted as a critical accelerator to operationalize Cameroon’s preexisting but under-implemented 2021 National Policy and Guidelines on Catch-up Immunization. However, centralized financial control created top-down pressures that were mitigated through bottom-up co-creation during local micro-planning. Operationally, reducing MOV required a shift from passive screening to active “Catch and Vaccinate” models, necessitating context-specific delivery adaptations in conflict zones and island populations. Despite these operational successes, stakeholders expressed deep concern regarding the long-term institutionalization due to an impending fiscal cliff. The system’s heavy reliance on external donor financing threatens the sustainability of community health workers’ incentives essential for demand generation. Furthermore, while the parallel IASO digital platform enabled real-time geolocation of missed children, it created double-reporting burdens, highlighting the structural challenge of synchronizing campaign tools with the national routine health information system. Ultimately, while recovery funding can successfully catalyze national policies and drive immediate equity gains, sustained resilience requires an urgent transition to domestic financing, the embedding of adaptive service delivery models into routine primary care, and the harmonization of digital tracking systems.
Auteurs
- Jean Christophe Fotso
-

Adalbert Tchetchia
Voir le profil | Plus d’articles - Ferdinard Ngong
- Victoria Ngako
- Olaitan Elihou Adje
Langues
- Anglais
Année de publication
2026
Type
Catégories
Pays
Mots-clés
Régions de l'OMS
Catch-up reports and briefs
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Cette ressource est incluse dans le tableau suivant:
| Titre | Auteur | Année | Type | Langue |
|---|---|---|---|---|
| “The opportunity to catch up”: from emergency response to immunization sustainability in Cameroon | Jean Christophe Fotso, Adalbert Tchetchia, Ferdinard Ngong, Victoria Ngako, Olaitan Elihou Adje | 2026 | Journal article | Anglais |
| Catching up in crisis: implementation of the big Catch-Up initiative in Yemen within a context of fragile routine immunization systems | Sheikh Abdulhafed Al-Shoteri, Alyssa Sharkey, Abdulla Salem Bin Ghouth, Iman Ali Mahmoud Ba-Saddik, Maysa Saeed AlNoban, Ali Ahmed Alwaleedi, Suha Abdullah Saleh, Nayf Radman Hamdan Akil | 2026 | Journal article | Anglais |
| Evaluation Report of the Big Catch-Up (BCU) Strategy in Mozambique: Experiences, Results, and Recommendations | UNICEF | 2026 | Case study | Anglais |
| Evaluation report on Strengthening Immunization Services to Reach and Recover Zero-Dose Children in Mozambique Through the Use of Digital Tools | UNICEF | 2026 | Case study | Anglais |
| Implementing the Big Catch-Up to close immunization gaps and adjust systems for restoring vaccination coverage: lessons from five countries | World Health Organization, The Alliance for Health Policy and Systems Research | 2026 | Report | Anglais |
| Reaching zero-dose children: lessons learned from the planning, implementation, and monitoring of Nigeria’s Big Catch-up initiative | Chisom Obi-Jeff, Abdulazeez Opeyemi Abdulganiyu, Chinyere Okeke, Chidinma Ahunam, Christianah Olanrewaju, Muhammed Tahir Muhammed, Rachael Oluropo, Michael Arowosegbe, Funmilayo Oguntimehin, Benjamin Uzochukwu | 2026 | Journal article | Anglais |
| Real-Time Monitoring Beyond the Big Catch-Up | UNICEF, World Health Organization (WHO), Gavi, the Vaccine Alliance, HealthEnabled | 2025 | Report | Anglais, Français |
| The Big Catch-up: Case study of immunization activities in Bauchi and Rivers States, Nigeria | Brooks Insights, Health Policy and Research Group | 2026 | Case study | Anglais |
| The Big Catch-up: Case study of immunization activities in Cameroon | Evidence for Sustainable Human Development Systems in Africa (EVIHDAF) | 2026 | Case study | Anglais |
| The Big Catch-up: Case study of immunization activities in Punjab and Sindh, Pakistan | Center for Economic Research (CERP), Rayn Consulting Group | 2026 | Case study | Anglais |
| The Big Catch-up: Case study of immunization activities in Tanzania | Fausta Michael, Mariam M. Mirambo, Mbonea Mbwambo, Victor Mtaki, Farhat S. Salaeh, Harrison D. Mariki, Domenica Morona, Stephen E. Mshana | 2026 | Case study | Anglais |
| The Big Catch-up: Case study of immunization activities in Yemen | Building Foundation for Development, University of Aden, University of Hadramout, Higher Institute of Health Sciences | 2026 | Case study | Anglais |
| Validating Progress Towards Closing Immunity Gaps in South Sudan - Rapid Convenience Monitoring: Findings and Priority Actions | World Health Organization (WHO), South Sudan Ministry of Health | 2026 | Report | Anglais |