What is melioidosis? The deadly disease spreading in Australia

Experts say prevention is key

A rare soil-borne disease is infecting people in far North Queensland. Here’s everything you need to know about melioidosis.

There have been more than 90 confirmed cases and 15 deaths from melioidosis this year alone in Queensland.

The bacteria usually live harmlessly in soil and freshwater, so what’s behind the outbreak?

What is melioidosis?

The bacteria Burkholderia pseudomallei can infect humans or animals through cuts, scratches, drinking contaminated water, or breathing in dust or water droplets.

The bug can cause superficial skin infections or abscesses, fever, headache, trouble breathing, chest and muscle pain, confusion, seizures, or a lung infection which can develop into pneumonia. 

As per the Herald Sun, Queensland's Tropical Public Health Services director Dr Jacqueline Murdoch said “Most people are still getting it from breathing it in so when there’s that heavy rain, the bacteria becomes airborne and people breathe it in.” 

“Most of the people we’re seeing are having severe disease with pneumonia or infection in their blood stream.”

The bug can cause superficial skin infections or abscesses, fever, headache, trouble breathing, chest and muscle pain, confusion, seizures, or a lung infection which can develop into pneumonia. Image: Pexels

Symptoms typically develop within one to four weeks after infection, and are commonly treated with intravenous antibiotics followed by oral antibiotics.

The infection is rare and often misdiagnosed as its symptoms are similar to many other diseases.

In Queensland, around 0.6 per 100,000 people contract melioidosis annually, but the disease is considered endemic to other parts of northern Australia too.

There have been 28 reported cases in the Northern Territory since October which, unlike case rates in Queensland, is lower than in past rainy seasons.

The infection is rare and often misdiagnosed as its symptoms are similar to many other diseases. Image: iStock

Anyone can get melioidosis, but it is rare in healthy adults and children.  The mortality rate in Australia is less than 10 per cent and people with diabetes, liver and kidney issues, cancer, and others who are immunocompromised are at greater risk 

Why is there an outbreak of melioidosis in Australia?

The recent melioidosis cases in North Queensland are likely linked to the heavy rainfall and flooding throughout the area, as the bacteria can come to the surface of soil during these events.

Murdoch said her team and health bodies “are yet to pinpoint exactly why we are seeing so many cases now, and there are likely to be many factors at play.”

“We’re investigating why there are such high numbers this year and we don’t really know exact reasons why, (but) certainly the climate has something to do with it”, she added. “Such a big rainy season last year is likely contributing to the high numbers this year.”

56 per cent of cases between February 2024 and February of this year have been in Cairns and Hinterland, and 33 per cent were in Townsville.

The recent melioidosis cases in North Queensland are likely linked to the heavy rainfall and flooding. Image: iStock

How to protect yourself against melioidosis

Wearing personal protective equipment (PPE) when in muddy and wet areas, or when using a hose or high-pressure cleaner can help protect against infection. These include: 

• Gloves and boots 
• A respirator 
• A covering over wounds

The physician said prevention and early detection are key, “so people who have a fever, trouble breathing or a cough in particular, need to present early to their GP or (emergency department) to be assessed because it is a very serious disease and it can progress very quickly.”

Originally published as What is melioidosis? The deadly disease spreading in Australia