Diphtheria in South Africa 2025 to date
The Centre for Respiratory Diseases and Meningitis (CRDM), National Institute for Communicable Diseases (NICD) in South Africa report three new laboratory-confirmed cases of toxigenic respiratory diphtheria, one from Limpopo, one from Mpumalanga and one from the Western Cape as of April 13.
Between 1 January 2024 and 13 April 2025, 43 confirmed cases of respiratory diphtheria, 1 probable respiratory diphtheria case and 40 asymptomatic carriers of toxigenic C. diphtheriae, detected during contact tracing, have been identified in South Africa.
Western Cape province accounts for the bulk of cases with 31, or 72 percent of the total.
The median age of cases of confirmed respiratory diphtheria was 28 years (range: 2–55 years), with 74% (32/43) being 18 years and older. The overall case-fatality ratio (CFR) among probable and confirmed respiratory diphtheria cases was 20% (9/44).
Of the 43 respiratory diphtheria cases, 10 cases were among children 12 years of age and under. Vaccine history is available for 3 of these. One symptomatic case (aged 9 years) had only received three infant doses of vaccine but no booster doses and the other two were reported as unvaccinated.
Respiratory diphtheria is a vaccine-preventable illness caused by toxigenic C. diphtheriae (and more rarely C. ulcerans or C. pseudotuberculosis), and can occur in persons of all ages.
The clinical presentation includes the following signs and symptoms:
sore throat
low-grade fever
AND an adherent membrane of the nose, pharynx, tonsils, or larynx – the membrane is greyish-white and firmly adherent to the tissue
AND/OR enlarged glands in the neck (bull neck)
toxin-mediated systemic signs including myocarditis, polyneuropathy and renal damage