New review shows the need to focus on antibiotic resistance in the environment

Antibiotic resistance in the environment is not well studied, which may have consequences for human health, according to research.

A review of more than 13,000 of studies into antimicrobial resistance – the ability of organisms to resist antimicrobial treatment – over three decades found less than 750 concerning the spread of antibiotic resistance in air, water and green spaces. 

The bulk of these studies focused on wealthy countries, and on freshwater settings, while low-income regions and other types of environmental settings have to date been overlooked, results showed.

Action is needed to address the knowledge gap, experts say, to avoid letting antibiotic resistance spread in under-studied environments. 

These might include monitoring the impact of wastewater release, understanding the impact of climate change on atmospheric pollutants, and the exchange of antibiotic-resistant bacteria between land, air and sea.

The study, led by the University of Surrey and involving the University of Galway and the Royal (Dick) School of Veterinary Studies, found that one-third of the studies came from China, followed by the US. 

Fewer than 1 per cent were led by researchers in countries such as Afghanistan, Ethiopia, and Uganda, where the impact of antibiotic resistance on health is likely to be highest, according to the study in published in Environment International.

The research team, which numbered more than 50 scientists, was surprised to also uncover an absence of studies linking antibiotic resistance to climate change and microplastics.

While this trend may have shifted in last couple of years as the field has emerged, it is unlikely to have changed substantially, leaving key questions unanswered.

They found that antibiotic-resistant bacteria are most often detected in freshwater and soil, particularly in places exposed to pollution from wastewater or manure. 

Two bacteria were the most studied organisms - Escherichia coli and Pseudomonas - while genes conferring resistance to medicines, including sulphonamides, tetracyclines and beta-lactams, were prominently researched.