Antibiotic Usage Linked to Antibiotic Resistance Genes in Human Gut Microbiome

Widespread usage of antibiotics is linked to higher levels of antibiotic resistance genes (ARGs) in the human gut microbiome, according to a study appearing in Nature Communications this week. The use of antimicrobials has been shown to drive the evolution of resistance in pathogenic microbes, but the impact on the microbiome is poorly understood. In the new study, a team led by scientists from Chung-Ang University in Korea and the UK's Earlham Institute surveyed ARGs in 8,972 metagenomes, including more than 3,000 gut microbiomes from healthy people not taking antibiotics. They uncover highly significant correlations between both the total ARG abundance and diversity and per capita antibiotic usage rates across 10 countries spanning three continents and show that these correlations are principally driven by mobile resistance genes embedded in a central network component dominated by commensal organisms. The researchers also discover that individual human gut ARG profiles cluster into two types, including one that is associated with certain classes of resistance.