A person has died of diphtheria in the Northern Territory. This is Australia’s first reported diphtheria death since 2018.
Diphtheria has been spreading in the Northern Territory, South Australia, Western Australia and Queensland over the past few months, according to the Victorian Department of Health. There have been 84 cases between 1 January to 14 April 2026. Of these cases, 91 per cent have been in Aboriginal and Torres Strait Islander people.
Dr Milena Dalton, Burnet Institute Head of Immunisation and Health Systems Strengthening, said the spread of the diphtheria outbreak across different states are "deeply concerning", adding: "This is no longer an isolated outbreak and it highlights how quickly vaccine-preventable diseases can re-emerge when there are immunity gaps."
Dr Dalton, a childhood vaccine and immunisation expert, says that the most important message is that diphtheria is preventable. Childhood vaccination coverage is important, but protection can reduce over time. Teenagers and adults must be kept up to date with boosters. However, this is more difficult in remote and under-served communities.
Dr Dalton added: "The fact that this outbreak is affecting Aboriginal communities points to the need for a rapid and culturally safe public health response.
"That means working with Aboriginal community-controlled health services, trusted local leaders and frontline workers to make testing, treatment and vaccination as accessible as possible.
"Getting tested, treated and vaccinated protects individuals, families and the wider community."
