Protocol for MpoxCARE Study: Evaluating Immunization Strategies in Mpox Outbreaks

Overview

The MpoxCARE study aims to validate novel immunodiagnostic assays for detecting Mpox-specific antibodies and assess Rwanda's vaccine cold chain capacity to support rapid Mpox vaccine deployment. This comprehensive evaluation addresses urgent public health needs amid rising Mpox cases in Central Africa, particularly the Democratic Republic of Congo and neighboring countries.

Background

Mpox is caused by the human Monkeypox virus, transmitted via close contact with infected animals or humans, presenting with fever, lymphadenopathy, and characteristic rash. Two viral clades exist: Clade I (Central Africa) with higher virulence and Clade II (West Africa), with the 2022 outbreak caused by subclade IIb lineage B.1. The 2024 resurgence in the DRC involves clade Ib strains with increased human transmission. Vaccination with ACAM2000, MVA-BN, or LC16 is recommended for high-risk individuals or post-exposure prophylaxis, but immune correlates of protection remain unclear.

Data Highlights

Between January 2024 and February 2025, 21,113 confirmed Mpox cases and 70 deaths were reported in Central Africa. Rwanda reported 127 cases by October 2025, contrasting with 34,000 cases in the DRC. The WHO allocated 1.45 million USD in August 2024 for smallpox vaccine access in the region. Antibody titres from smallpox vaccination have been shown to persist for decades, but their correlation to Mpox protection is not fully understood.

Key Findings

• The study will validate an ELISA assay for detecting anti-Mpox IgG antibodies in a Rwandan population, ensuring sensitivity across clade 1a and clade IIb strains.
• A prototype blood-based lateral flow test (LFT) will be evaluated for point-of-care detection of Mpox-specific antibodies.
• Biological samples and clinical metadata will be collected from volunteers with known Mpox exposure, vaccination, or no exposure to establish assay accuracy.
• The vaccine cold chain capacity in Rwanda will be assessed to determine readiness for rapid Mpox vaccine deployment without disrupting routine immunizations.
• Rwanda's robust public health infrastructure and detailed vaccination records provide a strong foundation for generalizable findings applicable to the wider Central African region.

Clinical Implications

Validated immunodiagnostic tools will enable accurate estimation of Mpox seroprevalence, guiding targeted vaccination strategies. Understanding cold chain capabilities ensures effective vaccine distribution during outbreaks, minimizing disruption to existing immunization programs. These insights support evidence-based public health responses to control Mpox spread in endemic and outbreak settings.

Conclusion

The MpoxCARE study addresses critical gaps in Mpox diagnostics and vaccine deployment infrastructure, providing essential data to inform outbreak control measures in Central Africa. Its findings will enhance preparedness and response strategies for current and future Mpox emergencies.

References

1. WHO 2022 -- Declaration of Public Health Emergency of International Concern
2. African CDC 2024 -- Public Health Emergency of Continental Security Declaration
3. University of Birmingham -- Development of Mpox-specific ELISA
4. Rwanda Biomedical Centre -- Vaccine Cold Chain Management