Antimicrobial usage sparks warning over increased resistance

University of Queensland research has found antimicrobial usage is significantly higher in affluent communities in Australia.

Samples have been collected from 50 wastewater treatment plants in locations across Australia servicing about 11.3 million people.

Research has found antimicrobial usage is notably higher in affluent communities across Australia.

Dr Jake O’Brien from UQ’s Queensland Alliance for Environmental Health Sciences said the team screened samples for approximately 100 antimicrobial compounds and compared the findings with socioeconomic factors linked to the locations.

“These factors included income, education, occupation and housing, to identify potential drivers of antimicrobial use,” Dr O’Brien said.

Antimicrobials are drugs, chemicals or substances that kill, inactivate, or slow the growth of microbes – including bacteria, viruses, fungi and parasites.

“Antibiotics like cephalexin, ciprofloxacin, and sulfamethoxazole were detected in 100 per cent of samples, which suggests widespread use across Australian communities,” Dr O’Brien said.

“The five most used antimicrobials or breakdown products were amoxicilloic acid, cephalexin, ciprofloxacin, sulfapyridine, and sulfamethoxazole – and each were detected in more than 90 per cent of samples.”

Dr O’Brien said Australia has one of the highest per capita rates of antimicrobial usage among high-income countries.

“Extensive use may pose a risk for the development of antimicrobial resistance, which is a critical global health challenge projected to cause up to 10 million deaths annually by 2050,” he said.

PhD Candidate Jinglong Li said this was the first nationwide survey of various antimicrobials and their breakdown products in Australian municipal wastewater.

“Traditional data sources, such as the Pharmaceutical Benefits Scheme, provide valuable insights but are primarily focused on prescription data, which doesn’t capture the full range of antimicrobials in use,” Mr Li said.

“Additionally, they don’t explain the connection between antimicrobial usage and socioeconomic factors.

“Using socioeconomic data from the 2021 Australian Census, we found clear disparities in antimicrobial use based on socioeconomic status.”

Mr Li said the findings fill gaps in understanding community antimicrobial use and provide policymakers with insights for creating programs that address disparities, reduce misuse, and combat antimicrobial resistance.