Heat Driving Rise in Serious Salmonella Cases Across Queensland

Queensland’s warming climate could bring a surge in serious food-borne illness, with new research linking rising temperatures to an increase in dangerous Salmonella infections.

The study, led by James Cook University PhD candidate and infectious diseases physician Dr Naveen Manchal, analysed a decade of health and climate data to better understand how heat impacts disease patterns.

“We investigated the link between rising temperatures and heatwaves across Queensland and cases of Salmonella and Campylobacter that had progressed to the bloodstream, a condition known as bacteraemia,” Dr Manchal said.

While both bacteria commonly cause gastroenteritis, bacteraemia is far more severe and often requires hospitalisation. Researchers examined more than 1,000 Salmonella cases and 234 Campylobacter cases recorded between 2010 and 2019.

The findings revealed no strong link between temperature and Campylobacter. However, Salmonella infections showed a clear and concerning trend.

“In Southeast Queensland, each 1°C rise in mean temperature increased the risk of Salmonella bacteraemia by 8 to 20 per cent. Maximum temperatures showed a similar pattern, with the risk rising up to 16 per cent,” Dr Manchal said.

“The effect was even stronger in the Tropical North, where a 1°C increase in mean temperature was associated with an 18 per cent rise in cases, peaking at 27.2°C. When maximum temperatures climbed above 28°C, the risk jumped sharply, increasing by 11 to 105 per cent for each additional degree.”

Heatwaves further intensified the risk.

“During extreme heat events, Salmonella bacteraemia rose by 31 per cent for every degree increase in maximum temperature,” Dr Manchal said.

Researchers warn that as temperatures continue to rise, Queensland’s health system may face increasing pressure, highlighting the need for stronger food safety and climate adaptation measures.

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