Scientists say “a reservoir of disease” is being created after discovering bacteria that naturally occur in rivers are becoming resistant to antibiotics due to the impact of sewage.

Researchers at the University of Suffolk said bacterial strains found on the non-tidal section of the River Deben in Suffolk had acquired resistance by exchanging DNA with antibiotic resistant E. coli.

Some bacteria have become resistant to the antibiotic carbapenem, which is used as the last line of defence in fighting infections already resistant to traditional antibiotics.