A two-case cluster of toxigenic Corynebacterium diphtheriae with molecular linkage
DOI:
https://doi.org/10.63719/imrj.2026.12.01.009Abstract
Diphtheria is a vaccine-preventable disease that continues to cause sporadic outbreaks in Malaysia, particularly among under-immunised populations. We report two temporally linked cases of toxigenic Corynebacterium diphtheriae presenting to a tertiary hospital in southern Malaysia. The first involved a 44-year-old adult male who was brought in deceased with extensive upper airway pseudomembrane formation. Two days later, a four-month-old infant presented with severe respiratory distress and required intensive care. Microbiological investigations confirmed toxigenic C. diphtheriae in both cases. The temporal clustering of these cases raised the possibility of an epidemiological association between them. Molecular typing using pulsed-field gel electrophoresis (PFGE) demonstrated indistinguishable strain profiles, implying circulation of a common strain and a possible shared source. These cases highlight the continued clinical relevance of diphtheria and the role of molecular methods in identifying strain linkage. Early recognition, strict infection prevention measures, and sustained vaccination coverage remain critical to preventing morbidity, mortality, and secondary transmission.
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