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, says:
"This is a tragic reminder that diphtheria is not a disease of the past. It is rare in Australia because vaccination works, but when immunity gaps emerge, particularly in communities facing barriers to healthcare, vaccine-preventable diseases can return with devastating consequences.
Dr Dalton says that 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.
"This outbreak is a reminder that vaccines can only protect communities when people can access them,” says Dr Dalton. “In remote and under-served communities, that means outreach, trusted local services, clear information, and enough workforce support to deliver boosters quickly."
