This Environment Agency and National Laboratory Service-funded MRes study is hoping to determine levels of antibiotic resistant E. coli in the environment and identify processes that might contribute to high levels of resistance.

Antimicrobial resistance (AMR) has become an increasing threat to global public health with waterways and systems possibly playing an important role in its development and spread.

For example, frequent bathers have an increased risk of carrying AMR bacteria in their faeces, and previous research has found that E. coli resistant to cefotaxime (an important antibiotic) are present in coastal waters at high enough levels to pose a threat to water users.

By identifying the process that might lead to the prevalence and dissemination of these resistant bacteria, this study will inform strategies to reduce environmental AMR transmission.

E. coli was chosen as the target organism for multiple reasons. It is easily and quickly cultured and E. coli is already used as a faecal indicator under the 2006 bathing water directive.

The World Health Organization recently recognised Enterobacteriaceae with resistance to 3GC or carbapenems (commonly used antibiotics) as a critical priority for research and the development of new antimicrobials. Studies have also shown that 3GC-resistant E. coli are found at high levels in coastal bathing waters, with an estimated 6.3 million people exposed in England and Wales in 2012.

Water samples have been collected from 10 different bathing sites in England which represent agricultural, urban, and mixed catchments. Microbial source tracking tests are being conducted to identify whether sources of bacterial pollution are from human, livestock, seabird, or dog-based origins.