Northern and Central Australia Diphtheria Outbreak 2026

Information for NSW Residents

Why is there concern about diphtheria right now?

There is currently an outbreak of diphtheria in the Northern Territory, Western Australia, South Australia and Queensland.

• This is the largest outbreak since national reporting began in 1991
• Over 90% of cases have occurred among Aboriginal or Torres Strait Islander people
• There have been no cases reported in NSW in 2026 as of 27 May
• You can find affected areas on the Australian Centre for Disease Control (CDC) website
• You can see current case numbers in the CDC epidemiology update reports

What is diphtheria?

Diphtheria is a serious illness that can be prevented with vaccination.

• Before vaccines were introduced, it was a major cause of death in children
• It is caused by bacteria (Corynebacterium diphtheriae in the current outbreak)
• It can affect the:
• throat and nose (respiratory diphtheria), or
• skin (cutaneous diphtheria)
• Vaccination helps protect against severe illness by blocking the toxin produced by the bacteria.

For more information about diphtheria, see the diphtheria fact sheet

What is being done about the outbreak?

• Health authorities across Australia are responding to the outbreak.
• Affected states and territories have activated full public health responses to the outbreak, with support from the Commonwealth government.
• NSW Health has issued a clinician alert to inform health professionals.
• In addition to National Immunisation Program-funded vaccines, NSW Health is funding boosters for Aboriginal and Torres Strait Islander people who have not had a dose in the last 10 years.
• Vaccination recommendations can be complex. Speak with your GP or Aboriginal Medical Service to check if you need a vaccine.
• If you are travelling to or moving to affected areas, you should consider a booster if you have not had one in the last five years. These are funded for Aboriginal and Torres Strait Islander people in NSW.
• NSW Health is working with the Aboriginal health sector to support diphtheria prevention and preparedness.

What can I do to stay safe?

Please see the latest NSW Health diphtheria vaccination advice​ for Aboriginal people and travellers to outbreak-affected areas. 

You can take simple steps to protect yourself and others.

• Check your vaccination
• Speak with your GP, pharmacist or Aboriginal Medical Service to check your vaccination history
• Get vaccinated if you need a primary course or booster.
• Before you travel
• Talk to a health professional if you are travelling to affected areas, you may need a booster dose.
• Look after your health
• Aboriginal people with a sore throat should see a GP or Aboriginal Medical Service for testing and treatment
• Sore throats can also be caused by other infections (like Strep), which can lead to serious health problems if untreated.
• Care for wounds
• Keep cuts and wounds clean and covered
• See a doctor if a wound shows signs of infection.

For more information

• Visit Healthdirect for general health advice
• See the diphtheria fact sheet
• Check the CDC website for outbreak updates.