Bacterial species, genes being identified for study examining antibiotic resistance in wastewater effluent

SCCWRP and its partners have begun working to confirm the identity of antibiotic-resistant bacteria and bacterial genes in treated wastewater effluent for an ongoing study examining whether this material is being discharged in viable form into the environment following treatment processes.

The confirmation phase, which began in October, will provide a deeper understanding of which antibiotic-resistant bacteria are surviving treatment and whether there are differences among the 10 treatment plants participating in the study.

The study was launched in 2017 to provide a baseline understanding of the prevalence of antibiotic-resistant bacteria and genes in wastewater effluent at Southern California treatment facilities. In particular, if antibiotic-resistant genes are surviving treatment processes that destroy most bacterial cells, they could get discharged into aquatic systems, where they could get taken up by pathogenic bacteria – a phenomenon that could create multidrug-resistant “superbugs”.

During the confirmation phase of the study, researchers are identifying more than 2,500 antibiotic-resistant isolates generated during culture sampling.

The bacteria also are being tested for multi-drug resistance using standard antibiotic resistance screening tests.