Meta-analysis addressing the characterization of antibiotic resistome in global hospital wastewater

Hospital wastewater (HWW) is a significant environmental reservoir of antibiotic resistance genes (ARGs). However, currently, no comprehensive understanding exists of the antibiotic resistome in global HWW. In this study, we attempted to address this knowledge gap through an in silico reanalysis of publicly accessible global HWW metagenomic data. We reanalyzed ARGs in 338 HWW samples from 13 countries in Africa, Asia, and Europe. In total, 2420 ARG subtypes belonging to 30 ARG types were detected, dominated by multidrug, beta-lactam, and aminoglycoside resistance genes. ARG composition in Europe differed from that in Asia and Africa. Notably, the ARGs presented co-occurrence with mobile genetic elements (MGEs), metal resistance genes (MRGs), and human bacterial pathogens (HBP), indicating a potential dissemination risk of ARGs in the HWW. Multidrug resistance genes presented co-occurrence with MGEs, MRGs, and HBP, is particularly pronounced. The abundance of contigs that contained ARG, contigs that contained ARG and HBP, contigs that contained ARG and MGE, contigs that contained ARG and MRG were used for health and transmission risk assessment of antibiotic resistome and screened out 40 high risk ARGs in the global HWW. This study first provides a comprehensive characterization and risk of the antibiotic resistome in global HWW.