The South African National Institute for Communicable Diseases (NICD) has reported two additional laboratory-confirmed cases of toxigenic diphtheria in the Western Cape, adding to a cluster of infections that has claimed the life of one child.
Between December 29, 2025 and March 29, 2026, health authorities identified 12 confirmed cases of respiratory diphtheria and two asymptomatic carriers of toxigenic C. Diphtheriae. All of these cases and carriers were located within the Western Cape. In a separate development this year, a single case of cutaneous toxigenic diphtheria was reported in Gauteng.
The clinical profile of the outbreak
While diphtheria is often associated with childhood, the current data shows a significant impact on adults. The median age for confirmed respiratory cases was 28 years, with a range spanning from 7 to 36 years. Three-quarters of the patients (9 out of 12) were 18 years or older.

Despite the prevalence among adults, the disease’s severity remains a critical concern for the youngest patients. The overall case-fatality ratio for respiratory diphtheria in this group was 8%, with the only recorded death occurring in a child between the ages of 0 and 9.
Medical guidelines emphasize that treatment, contact tracing, and chemoprophylaxis must commence prior to laboratory confirmation. Because the diphtheria anti-toxin (DAT) is most effective when administered early to neutralize unbound toxins, delaying treatment until lab results return can be life-threatening.
Identifying the symptoms
Respiratory diphtheria is a vaccine-preventable illness caused by toxigenic C. Diphtheriae, though it can more rarely be caused by C. Ulcerans or C. Pseudotuberculosis. The disease can manifest across all age groups.
Clinicians and the public are advised to glance for a specific combination of signs:
- Sore throat and low-grade fever.
- The presence of a greyish-white membrane that is firmly adherent to the tissue of the nose, pharynx, tonsils, or larynx.
- Swollen glands in the neck, often referred to as a “bull neck.”
Beyond these localized symptoms, the bacteria produce toxins that can lead to severe systemic complications, including renal damage, polyneuropathy, and myocarditis (inflammation of the heart muscle).
Treatment and public health response
Management of the disease requires a dual approach: antibiotics, such as penicillin or azithromycin, are used to clear the organism from the throat and stop the spread to others, while diphtheria anti-toxin (DAT) is used to neutralize the toxins already in the system. The specific dosage of DAT depends on the severity and duration of the illness.
The Western Cape Government has urged clinicians who suspect diphtheria to contact the NICD 24-hour Clinician Hotline at 0800 212 552. Immediate priorities for healthcare providers include collecting throat swabs using correct procedures and completing case investigations to help authorities identify and trace further contacts.
Frequently Asked Questions
Who is most at risk in the current outbreak?
While the majority of confirmed respiratory cases in the Western Cape have been adults (75% aged 18+), the only recorded fatality was a child aged 0–9, indicating high risk for unvaccinated or under-vaccinated children.
Can someone carry the bacteria without being sick?
Yes. The NICD identified two asymptomatic carriers during contact tracing, meaning individuals can spread the bacteria even if they do not show clinical symptoms.
How can communities better support the identification of vaccine-preventable illnesses in high-risk areas?






