It’s the quiet killer that lurks in northern Australian gardens.

Melioidosis is a bacterial infection spread through contact with contaminated soil, water, or even air. 

The risk is heightened in tropical areas after heavy rains or cyclones, and in some cases, it can be deadly. 

In the past 12 months, 80 people contracted the disease in the Northern Territory, and five people have died.

But researchers at the 10th World Melioidosis Congress, held in Darwin last week, say a vaccine may not be far off.

Professor David Wagner, who travelled to Darwin from Northern Arizona University in the United States, said the development of a vaccine was rapidly advancing.

“We are hopeful through a joint US-Australia collaboration that we’ll be putting shots in arms up here in the Darwin area … in the next year or two,” he said. 

The Menzies School of Health Research in Darwin is internationally recognised for its research into melioidosis. 

Senior researcher Mark Mayo said advancements in the treatment of the disease meant “more people are living longer when they get infected”. 

Concerns the disease is spreading beyond Australia and Asia

Symptoms of melioidosis include chest infection and breathing difficulties, as well as headaches, non-healing skin sores, confusion and joint swelling. 

Researchers believe the disease developed in northern Australia and is commonly found in South-East Asia, with recent outbreaks in Hong Kong.

Professor Wagner said it was recently discovered in the US for the first time, in the state of Mississippi, raising concerns the disease is potentially more widespread than previously thought.

“That sort of changed the dynamic there,” he said. 

“We know it’s there now, so we’re going out to try and find it in other areas of the US.”

Darwin health experts prepare ahead of wet season

Back home, researchers are working to combat the disease in northern Australia.

Professor Bart Currie, who leads the tropical and emerging infectious diseases team at Menzies School of Health Research, said this year’s early rains have put the team on “high alert” weeks earlier than usual.

“We’ve actually instituted some of our melioidosis preventative work in our emergency department in the hospital,” he said. 

“And in the laboratory we switched to our wet season protocol to really keep a lookout.”

Professor Currie urged residents in Darwin’s rural area to take care around bore water.

“If someone is living on a rural block where they have diabetes or are on cancer therapies — something that might suppress their immune system — it’s not wise to be drinking that bore water directly,” he said.

“Those people will often use bottled water or put a chlorinator or UV filter on their bore.”

Health advice has been issued to construction workers, after labourers in Cairns fell ill with the disease in 2021. 

“The environment gets disturbed by the construction and the bacteria propagates in the surface and also aerosolised when there’s heavy rain and winds,” Professor Currie said. 

The disease is usually transmitted via cuts in the skin, so it’s advised to wear gloves and closed-toed shoes when gardening.

It can also be inhaled or ingested, so reducing contact with muddy waters during the wet season, or washing it off immediately, is the best way to stay safe.