ANALYSING wastewater samples from several aged care and retirement homes in Adelaide, has uncovered worrying signs of antimicrobial resistance (AMR) in at least one facility, a University of South Australia study has found.

High levels of bacterial resistance against three common antibiotics – ceftazidime, cefepime and ciprofloxacin – were identified in one aged care residential home.

A second facility recorded above average levels of antimicrobial resistance to gentamicin.

The listed antibiotics are used to treat a variety of bacterial infections, including pneumonia, gynaecological, urinary and respiratory tract infections, and those affecting bones and joints.

Although the wastewater study was confined to three sites and 300 residents, the findings suggest a much wider problem, and are a clear warning to aged care facilities to implement stricter policies when it comes to medication use, said microbiologist, A/Prof Rietie Venter, who led the university’s study.

“As well as increasing death rates, AMR can lengthen illness recovery times, especially for immunocompromised people who make up a high proportion of people in aged care homes.”

Accurately monitoring the misuse and overuse of antibiotics in residential aged care homes is challenging, hence the use of wastewater-based surveillance, believed to be a first for this sector, Venter added. JG