Five more deaths in the Townsville and Cairns region have now bought the total death toll from this melioidosis outbreak to nine amongst dozens of cases. Melioidosis is caused by Burkholderia pseudomalleii which is a soil dwelling bacterium than can cause disease in humans when it enters the lungs or bloodstream via inhalation or cuts. Floods in this region have caused the bacterium to come to the surface and be mobilised by flood waters. The majority of the fatal infections appear to be due to inhalation of airborne droplets containing the bacteria. Residents should monitor for symptoms such as fever, difficulty breathing, shortness of breath or headaches, and contact a health professional. People should avoid flood waters and mud where possible or use protective clothing when in these areas.

Melioidosis is a rare disease, and while most people won’t be affected, outbreaks like this serve as an important reminder of the ongoing challenges posed by antimicrobial-resistant bacteria. Burkholderia pseudomallei is naturally resistant to multiple antibiotics, making rapid and accurate diagnostics crucial to ensuring timely treatment. Investing in better detection methods and new antibiotic treatments is essential—not just for this disease, but for strengthening our ability to respond to emerging bacterial threats in the future.

Unprecedented melioidosis case rates in the Cairns and Townsville regions this wet season is a cause for concern but not alarm. The melioidosis bacterium, Burkholderia pseudomallei, has lived in soil and water across much of northern Australia for millennia, including in most parts of Qld. Thanks to tireless public health campaigning, residents of the NT's tropical Top End, a global melioidosis hotspot, are very familiar with melioidosis - they know that cases spike following severe wet weather events, similar to what north Qld has experienced this wet season. Increased public awareness about melioidosis risk factors and symptoms, coupled with rapid diagnosis by public health laboratories, are crucial for rapid diagnosis and effective treatment of this potentially fatal disease.

The melioidosis bacterium, Burkholderia pseudomallei, is naturally resistant to most antibiotics, so it's vital that infections be diagnosed quickly so that the right drugs can be administered as soon as possible. On rare occasions, we have observed that this bacterium can evolve resistance towards these first-line antibiotics, including ceftazidime, meropenem, and amoxicillin-clavulanate, so it's important that infected individuals be regularly monitored for any signs of relapse, which should then prompt a change in antibiotic treatment

Melioidosis is caused by the bacterial species Burkholderia pseudomallei. The microbe lives in tropical soils and water and is most commonly observed in tropical regions. It’s quite well known in Queensland and the Northern Territory and could be described as endemic in these areas. Melioidosis becomes more common during natural disasters, especially flooding and is most likely to occur in muddy soils.

Infection is linked to bacterial cells coming into contact with wounds and can sometimes cause infections from inhalation of soil particles and drinking contaminated water. People who have weakened immune systems, diabetes, are elderly, or are heavy drinkers are most susceptible to melioidosis infections. About half of infections occur in diabetic people.

Despite its notoriety, infection is relatively rare and mostly occurs when susceptible people have significant contact with contaminated water or soil, such as during gardening or assisting with flood clean-up activities. Unfortunately, Melioidosis has a 20-50% fatality rate because the organism is very aggressive and resistant to antibiotics. As many as 90,000 people around the world die from melioidosis infections each year.

Burkholderia pseudomallei possess protein systems that act like spring-loaded poison daggers which are used to potentially infect and damage cells in a wide range of hosts including humans, animals and even plants. To avoid infection, it’s recommended that people wear protective clothing such as gloves and masks while gardening or working around muddy soil in areas known to host the bacteria and to take extra precautions if susceptible. 

If you have any cuts or abrasions or are diabetic, you should avoid working with soil and avoid contact with muddy soils. Water should be checked for contamination in areas known to have endemic melioidosis.

Melioidosis is a rare but potentially fatal bacterial disease caused by Burkholderia pseudomallei, which lives in soil and mud. Heavy rainfall and flooding can bring the bacteria to the surface, increasing the risk of human infection. Following recent major floods in Far North Queensland, Queensland Health has reported 81 cases and seven deaths so far this year, mostly in the Cairns and Townsville regions.

The bacteria can enter the body through open wounds, inhalation, or drinking contaminated water. Symptoms include fever, coughing, breathing difficulties, and skin infections. If untreated, melioidosis can lead to severe complications such as pneumonia or sepsis. Vulnerable groups include people with diabetes, chronic illnesses, weakened immune systems, or the elderly.

Diagnosis is made by isolating the bacteria from blood, urine, sputum, pus, or tissue samples. Treatment involves strong antibiotics to manage both acute infection and long-term bacterial eradication.

Residents in affected areas should take precautions such as wearing protective clothing, covering wounds, and avoiding contact with muddy floodwaters. There is currently no vaccine for melioidosis; however, preclinical trials are underway.

Melioidosis is a rare, tropical infection caused by a bacterium which lives in the soil – Burkholderia pseudomallei. It occurs in tropical areas and is much more common after heavy rainfall such as has recently been seen in Far North Queensland, although it can also occur in the dry season.

It most commonly presents as a severe chest infection (cough, fevers and chills) but can also affect the skin and internal organs. People with pre-existing health conditions like diabetes, kidney problems; who take immune-suppressing medicines; or people who are heavy consumers of alcohol are more at risk.

The infection does not respond well to common antibiotics given in the community, so if patients (particularly vulnerable ones) are not getting better after seeing their GP, then it is worth considering melioidosis during the wet season.

Preventing melioidosis is difficult. Vulnerable patients should avoid coming into contact with wet soil or water (eg gardening or pressure spraying hard surfaces) during the wet season, or wear protective equipment like masks, gloves or gumboots.

Reducing rates of chronic disease in patients in the tropics will help make the community less susceptible, but is a long-term goal. Until then, preventing exposure and seeking early medical attention are very important.

The melioidosis outbreak in Queensland highlights the risks of Burkholderia pseudomallei, particularly after heavy rainfall. This soil-dwelling bacterium can cause pneumonia, septicaemia, abscess formation, and neurological infections, especially in individuals with diabetes or weakened immunity. Early diagnosis and targeted antibiotic treatment are crucial. With climate change driving extreme weather events, enhanced surveillance, public awareness, and clinician education are vital for managing future outbreaks.

Melioidosis is one of the most common causes of fatal, bacterial, community-acquired sepsis and pneumonia in tropical Australia and case notifications are rising and incidence is becoming less predictable. Melioidosis is caused by the environmental bacterium Burkholderia pseudomallei and its growing health burden is at the intersection of changing climate, environment and land use.

Our team are leaders in Bps clinical and genomic epidemiology and environmental surveillance and are members of national and international consensus groups. We have identified and characterised environmental sources for melioidosis influencing health policy and improving clinical outcomes in communities in Australia and overseas. Evidence is emerging from our group that Bps mobility affected by changes in the environment is challenging our understanding of melioidosis epidemiology. This includes recent importation and spread of novel strains in urban centres and clinical clustering assumed to be due to urban encroachment and alteration of environments.

Given the impact of melioidosis is overrepresented in socioeconomically disadvantaged communities and individuals with chronic illness, predicting and planning melioidosis impact to address the rising incidence in Australia is more critical. The only way to predict escalating and changing melioidosis risk is through understanding how the disease reservoir is influenced by these changes.