PhageLand: Phage treatment and wetland technology asintervention strategy to prevent dissemination of antibiotic resistance in surface waters

Antibiotic resistance is a global problem. Resistant bacteria and resistance genes can spread further into the environment via wastewater. It is therefore important to investigate new ways of combating this spread.

Aim

The PhageLand project explored how viruses that infect bacteria (phages) could help remove harmful and antibiotic-resistant bacteria from wastewater, aiming for solutions usable worldwide.

Results

At TU Delft and in collaboration with European partners, the researchers first developed methods to find where resistance genes are located within phages, bacteria, or free-floating DNA present in wastewater. They found that after wastewater treatment, resistance genes mainly remain in free DNA and residual bacteria, not in phages. In lab tests, they showed that some phages could suppress microbial pathogens, but results were less clear in real wastewater. 

The researchers also helped design a pilot system in Poland using a mix of phages in a constructed wetland to clean sewage from these undesired microbes. While constructed wetlands can remove well nutrients and medicines, the phage supply did not clearly lower pathogen levels under the studied conditions. 

Follow-up

Although phages have promises to kill harmful bacteria, more work is needed to make them effective outside the lab to safeguard our water resources across the globe.