Australia’s peak medical body is urging people to check their vaccinations amid what health authorities have described as the country’s biggest diphtheria outbreak in decades.
A resurgence of the highly contagious disease, once considered close to eradication in Australia, has spread across three states including the Western Australia, Queensland and South Australia, and the Northern Territory, with 223 confirmed cases recorded so far.
One person in the Northern Territory has died, although the exact cause of death is still being investigated.
The Australian Medical Association has urged people to ensure they and their families are fully vaccinated and up to date with booster shots.
“Immunisation is one of the greatest achievements in modern medicine, but when vaccination rates fall, serious diseases, which we had largely eliminated, can make a come back,” AMA President Danielle McMullen said.
“We are seeing that risk play out with diphtheria.”
The current outbreak began in remote Aboriginal communities in the Northern Territory and has since spread across all five regions of the Territory.
Health authorities have linked the strain to smaller outbreaks previously recorded in Western Australia’s Kimberley region and North Queensland.
As of this week, the Northern Territory had recorded 133 cases, while Western Australia had reported 79. South Australia and Queensland have also confirmed cases, with six in SA and five in Queensland.
Federal Health Minister Mark Butler said the outbreak was a serious concern.
“This is probably the biggest diphtheria outbreak we’ve seen – certainly for decades,” he said.
“There’s no question this is serious.”
Children in Australia are routinely vaccinated against diphtheria at two, four and six months of age through the National Childhood Immunisation Program, with booster shots recommended later in life.
However, vaccination rates have fallen in recent years, with the number of fully vaccinated two-year-olds dropping below 90 per cent in 2024.
Health experts believe declining vaccination rates following the COVID-19 pandemic may be contributing to the outbreak.
Burnet Institute immunisation expert Milena Dalton described the scale of the outbreak as “deeply concerning”.
“This is no longer an isolated outbreak, and it highlights how quickly vaccine-preventable diseases can re-emerge when there are immunity gaps,” she said.
Diphtheria is spread through coughing, sneezing and contact with infected skin sores. Early symptoms can resemble a cold or flu, including fever and sore throat, but severe respiratory cases can make it difficult to breathe and may become life-threatening.
Before widespread vaccination campaigns began in the 1930s, diphtheria was one of the leading causes of death among Australian children, killing more than 4000 Australians between 1926 and 1935.
While antibiotics and antitoxins are used to treat the disease, experts warn vaccination remains the best protection. Even with treatment, up to one in 10 people with respiratory diphtheria can die.
Image: Shutterstock
