Resistome in the indoor dust samples from workplaces and households: a pilot study

In the indoor environment, bacteria may harbor a broad spectrum of antibiotic resistance genes (ARGs). These genes predispose to a susceptibility to the treatment of bacterial infections in both humans and animals worldwide. Current research on the presence of ARGs in bacteria focuses mainly on their presence in clinical samples from patients. However, the spectrum of ARGs in the dust bacteriome in households and workplaces has gone relatively unexplored. This pilot study aimed to analyze resistome in indoor dust samples from participants' households and workplaces (a pediatric hospital, a maternity hospital, and a research center) and compare two different approaches to ARGs analysis; high-throughput quantitative PCR (HT-qPCR) technique and whole metagenome shotgun sequencing (WMGS). In total, 242 ARGs were detected using HT-qPCR with the highest abundance of ARGs associated with the MLSB (macrolides, lincosamides, and streptogramin B) phenotype, MDR (multi-drug resistance) genes, and with resistance to aminoglycosides. A higher overall relative quantity of ARGs was observed in indoor dust samples from workplaces than from households. The highest relative quantity of ARGs was detected in the pediatric hospital. WMGS analysis revealed 36 ARGs, of which five were detected by both HT-qPCR and WMGS technique. Accordingly, the efficacy of WMGS approach to detect ARGs was lower than that of HT-qPCR. In summary, our pilot data revealed that indoor dust in buildings where people spend most of their time (households, workplaces) can be a great source of antimicrobial-resistant bacteria, which may potentially pose a health risk to both humans and animals.