Australia has recorded its first death from diphtheria in almost a decade, as the country grapples with the worst outbreak of the vaccine-preventable disease in decades.
In March, the Northern Territory (NT) declared a diphtheria outbreak with cases also in Western Australia, South Australia and Queensland. Cases began to increase in late 2025, with a sharp increase in February.
This year there have been 245 cases, the largest outbreak in Australia since 1991, mainly in isolated Indigenous communities.
On Tuesday, the Northwest Territories health minister said autopsy results from an overseas laboratory revealed diphtheria was the cause of a man’s death in April at the Royal Darwin Hospital, the first such case since 2018.
In recent weeks, the government has stepped up vaccination efforts in areas most at risk and the number of new cases is now falling, health officials said Tuesday.
“Our government has taken this situation very seriously and we are working hard to understand the causes and work to contain the situation,” said Northwest Territories Health Minister Steve Edgington.
Since March 30, 10,407 vaccinations have been carried out, he said.
Between January last year and May this year, the NT reported 163 cases of diphtheria, including 48 respiratory cases and 115 skin cases, which are transmitted through skin contact.
In March, Western Australia (WA) health authorities confirmed two cases of respiratory diphtheria, the first time in more than 50 years that Western Australia had recorded such cases.
Sixty per cent of cases this year are in the Northern Territory, followed by Western Australia at around 36 per cent, with a few cases in South Australia and even fewer in Queensland.
Authorities are urging affected communities to update their vaccinations, especially adolescents and adults who need to receive boosters.
NT health officials have opened pop-up clinics in Darwin, Katherine and Alice Springs to raise awareness of the vaccination campaign, as vaccines are “the most important measure to prevent, protect and reduce transmission”, NT Health said.
Both strains of diphtheria – respiratory and cutaneous – are preventable thanks to a vaccine, generally given to children – five doses between two months and four years of age – with a booster between 12 and 13 years of age.
Respiratory diphtheria often begins with fever or chills, a sore throat that can cause difficulty breathing and swallowing and be life-threatening.
Cutaneous diphtheria usually causes infected sores or ulcers on exposed parts of the body, which take time to heal but rarely lead to serious illness.
It appears that the last death from diphtheria was in 2018, according to national television channel ABC.
Last week, Australia’s chief medical officer, Professor Michael Kidd, declared diphtheria a communicable disease incident of national significance.
The government also announced a A$7.2 million program to boost vaccination and resources in affected areas.