Clinical Report: Diphtheria Outbreak and Vaccination Challenges in Guinea 2023

Overview

In the 2023 diphtheria outbreak in Guinea, 20.3% of suspected cases were confirmed by RT-qPCR, with an 8.9% fatality rate. Key risk factors included age under 15 years, lack of prior vaccination, and contact with infected individuals, while characteristic clinical signs such as whitish throat membrane and dyspnea were strongly associated with confirmed cases.

Background

Diphtheria is a potentially fatal infectious disease caused by Corynebacterium diphtheriae, preventable through vaccination. Despite global control efforts, re-emergence occurs in several regions, including Guinea, where vaccination coverage remains low. The 2023 outbreak in Guinea highlighted under-immunization, with only 54% coverage in young children and a significant number of suspected and confirmed cases. Early recognition of clinical signs and understanding risk factors are critical for effective disease management and reducing mortality.

Data Highlights

Key Findings

• Confirmed diphtheria cases exhibited high prevalence of sore throat (91%), fever (90%), whitish throat membrane (83%), throat redness (81%), and dyspnea (28%).
• Age under 15 years, absence of prior vaccination, and contact with diphtheria patients significantly increased risk of disease development.
• Whitish throat membrane and dyspnea were clinical signs significantly associated with diphtheria positivity.
• The overall case fatality rate was 8.9%, with most deaths occurring within 3 months of outbreak onset and shortly after hospital admission.
• Vaccination coverage in Guinea remains suboptimal, contributing to vulnerability and outbreak severity.

Clinical Implications

Clinicians should prioritize early recognition of hallmark signs such as whitish throat membrane and dyspnea in suspected diphtheria cases to enable prompt diagnosis and treatment. Strengthening vaccination programs targeting children under 15 years is essential to reduce disease incidence and mortality. Contact tracing and monitoring of exposed individuals can help mitigate transmission during outbreaks.

Conclusion

The 2023 diphtheria outbreak in Guinea underscores the critical need for improved vaccination coverage and heightened clinical awareness of characteristic symptoms to reduce disease burden and fatalities. Targeted public health interventions are vital to control re-emergence in vulnerable populations.

References

1. World Health Organization 2023 -- Diphtheria Epidemiology and Vaccination Data
2. National Agency for Food Safety Guinea 2024 -- Diphtheria Outbreak Report
3. Demographic and Health Survey Guinea 2018 -- Childhood Vaccination Coverage