The Northern Territory Centre for Disease Control report investigating an outbreak of diphtheria.
As of Wednesday, there have been four cases of respiratory diphtheria (3 in Darwin, 1 in Alice Springs) notified in the last week and 33 cases of cutaneous diphtheria notified since 2025.
“This is unusual, we haven’t had an outbreak in my 26 years in the Northern Territory,” NT Health Chief Health Officer Paul Burgess said.
Diphtheria is an infectious disease caused by the bacteria Corynebacerium diphtheria.
It is spread person to person by inhaling respiratory droplets and less commonly by direct skin contact of lesions of infected people.
The most serious infections are caused by a toxin produced by some types of the bacteria.
Subscribe to Outbreak News TV on YouTube
Respiratory diphtheria can include a sore throat and fever, and an adherent grey pseudomembrane that can cover the tonsils and mucosa of the pharynx, larynx, and nose. Enlarged anterior cervical lymph nodes and oedema of the surrounding soft tissue can cause a characteristic ‘bull-neck’ appearance. Untreated, respiratory diphtheria can be life-threatening.
Cutaneous diphtheria presents as chronic, nonhealing sores or shallow ulcers which may have a grey membrane.
Diphtheria vaccination protects against the disease and is very effective. It gives protection against disease by production of antibodies to the diphtheria toxin. Ensure children, adolescents and adults are up to date with appropriate DTPa or dTpa vaccination