Bacteria swap genes all the time, so it’s not surprising to find drug-resistant bacteria in the environment. The most vulnerable environments are urban water bodies that receive wastewater. Even if the wastewater has been properly treated, some resistance genes are able to pass through the treatment process intact. What this all means to human and ecosystem health is still a large unknown.

And it’s not just hospitals and nursing homes we need to worry about. Genetic engineering technologies are used in many applications, including biofuel fermentation, agriculture (crops and livestock), and environmental bioremediation. Discharge of genetic materials may enter the environment in a relatively uncontrolled manner, especially in countries with weak environmental protection regulations.

It’s not clear what the significance of the findings of this study are, but the authors state that their results may portend “a source of antibiotic resistance in humans."