Tracking antibiotic resistance

Sequencing plasmids can reveal the transmission of resistance among bacteria from patients in a clinical setting According to the World Health Organization (1), “Antimicrobial resistance…threatens the effective prevention and treatment of an ever-increasing range of infections caused by bacteria, parasites, viruses and fungi….A post-antibiotic era—in which common infections and minor injuries can kill—far from being an apocalyptic fantasy, is instead a very real possibility for the 21st Century.” Often, antibiotic-resistance genes acquired by bacteria are associated with mobile genetic elements that mediate their exchange between pathogens, or between commensal and pathogenic bacterial populations. Thus, the genetic context in which an antibiotic-resistance gene is placed can reflect its mobility within the bacterial population. Although the presence of resistance genes in clinical isolates can be detected with either polymerase chain reaction technology or high-throughput short–read length DNA sequencing, their precise genetic context may be overlooked because of the limitations of these methodologies. As Conlan et al. (2) demonstrate, the use of single-molecule long-read DNA sequencing can address this limitation and opens the way to track the transmission of antibiotic-resistant bacteria in a health care environment.