More Than 230 Cases Of Diphtheria Reported In Australia; Check Symptoms, Causes, Complications And More

Australia is currently dealing with its biggest diphtheria outbreak in decades, with more than 230 confirmed cases reported in 2026. Health authorities say that the rise has mainly affected areas in the Northern Territory and Western Australia, while additional cases have also been seen in Queensland and South Australia. The outbreak has pushed the government to increase vaccination efforts and provide extra funding for public health responses. Officials say that the disease, which was once considered rare in Australia, is making a comeback.

According to a report in ABC News, Federal Health Minister Mark Butler said, "This is a very serious outbreak of a very serious disease.

"It's important we control it but it's also important that people get vaccines into their arms in affected areas as quickly as possible because at the end of the day that is the most effective way to protect yourself and those around you."

Experts believe several factors may be behind the increase. Lower vaccination coverage in some communities, delays in booster doses, misinformation about vaccines, and limited healthcare access in remote regions, could be some of the possible reasons. Read on to know more about the bacterial infection.

What Is Diphtheria?

Diphtheria is a serious bacterial infection caused by Corynebacterium diphtheriae. It mainly affects the nose and throat, although it can also affect the skin. The bacteria produce toxins that can damage body tissues and spread through the bloodstream.

Before vaccines became common, diphtheria was one of the leading causes of illness and death in children. Today, vaccination has reduced cases in many countries, but outbreaks can still happen when immunisation rates fall.

The disease generally appears in two forms:

• Respiratory diphtheria: Affects the throat and airways and is considered more dangerous.
• Cutaneous diphtheria: Affects the skin and usually causes sores or ulcers.

Symptoms Of Diphtheria

Symptoms often appear two to five days after exposure, though timing may vary.

Common signs of respiratory diphtheria include:

• Sore throat
• Fever
• Swollen glands in the neck
• Weakness and tiredness
• Difficulty swallowing
• Trouble breathing
• Thick grey or white coating in the throat or on the tonsils

This coating can block the airway and make breathing difficult. It is one of the most recognised signs of severe diphtheria.

Skin diphtheria may cause:

• Painful sores
• Slow-healing ulcers
• Bluish or grey-looking patches on the skin
• Infection in existing wounds

Skin infections are usually less severe but still need treatment.

How Does Diphtheria Spread?

Diphtheria spreads from person to person. The infection can move through:

• Respiratory droplets: When an infected person coughs, sneezes, or talks, tiny droplets carrying bacteria can spread to others.
• Direct contact: Touching infected wounds or skin lesions may lead to transmission.
• Contaminated objects: Although less common, bacteria may survive on surfaces and objects touched by an infected person.

People can spread the infection even if symptoms are mild. In some cases, vaccinated individuals may still carry the bacteria, though vaccines help reduce severe illness.

Causes Behind The Current Outbreak

The recent rise in cases has raised concerns among public health experts. Several factors may have contributed:

• Reduced vaccination coverage: Some people missed routine childhood vaccines or booster doses over the years. Lower protection in communities increases outbreak risk.
• Vaccine misinformation: Health experts have pointed to misinformation around vaccines as one factor that may affect immunisation uptake.
• Limited healthcare access: Remote communities often face challenges such as fewer healthcare workers, delayed treatment, and lower access to vaccination services.
• Population movement: Travel and movement between regions may also help infections spread faster.

Possible Complications Of Diphtheria

Diphtheria is not just a throat infection. If treatment is delayed, the toxins produced by bacteria can affect different organs.

• Breathing problems: The membrane formed in the throat may block airways and reduce oxygen supply.
• Heart damage: Toxins can lead to inflammation of the heart muscle, a condition known as myocarditis.
• Nerve damage: Some people may develop weakness, paralysis, or problems with movement.
• Severe illness and death: Untreated respiratory diphtheria can become life-threatening, especially in people who are unvaccinated.

Preventive Measures To Stay Safe

Vaccination is the best way to protect oneself against diphtheria. The vaccine is typically given in combination with protection against tetanus and pertussis (DTP vaccine) during childhood, followed by booster doses. Health authorities continue to encourage people to stay up to date with their shots and booster doses.

Other prevention steps include:

• Wash hands regularly with soap and water
• Avoid close contact with infected people
• Cover the mouth while coughing or sneezing
• Seek medical care if symptoms appear
• Complete all recommended vaccine doses and boosters

Parents should ensure children receive routine immunisations on time, while adults should check if they need booster shots.

The current outbreak in Australia is a reminder that vaccine-preventable diseases can return when protection drops. Early detection, awareness, and vaccination remain the strongest tools in preventing further spread.

Disclaimer: This content including advice provides generic information only. It is in no way a substitute for a qualified medical opinion. Always consult a specialist or your own doctor for more information. NDTV does not claim responsibility for this information.