Plasmids are pieces of independent DNA that often carry multiple antibiotic resistance genes. Plasmids can jump from one bacterium to another, spreading that resistance. A team of French investigators now shows that bacteria that acquire plasmids containing resistance genes rarely lose them. The research is published in Antimicrobial Agents and Chemotherapy, a journal of the American Society for Microbiology.
In the study, the investigators focused on plasmids carrying resistance to extended spectrum cephalosporins. "Cephalosporins are antimicrobials that are critical to human health, as they are used to treat urinary tract, and other infections," said corresponding author Isabelle Kempf, DVM, head of the Mycoplasmology-Bacteriology Unit, the Agence Nationale de Securité Sanitaire, Université de Bretagne Loire, Ploufragan, France. The gene for resistance to extended spectrum cephalosporins is frequently carried on plasmids, often along with multiple genes for resistance to other antimicrobials.
The investigators inoculated pigs with an extended spectrum cephalosporin-resistant, non-pathogenic strain of Escherichia coli, and placed the pigs in pens with non-inoculated pigs. A plasmid in the E. coli carried the gene for extended spectrum cephalosporin resistance, as well as four other resistance genes. The investigators collected fecal samples from the pigs, at different time points following inoculation. From these, they grew 353 isolates of E. coli.
During the experiment, the pigs did not receive extended spectrum cephalosporin antibiotics. That meant that there was no selection pressure that might have favored the persistence of extended spectrum cephalosporin resistance in the bacterial populations. Nonetheless, all but three of the 353 isolates carried the resistance gene.
"Our results show that once a plasmid encoding resistance genes is transferred to a bacterial host, the probability that the bacteria will lose the encoded resistances is quite low, even absent a selective pressure," said Kempf
"Plasmids have developed sophisticated mechanisms to ensure their transmission to daughter cells during cell division," Kempf explained. "A better knowledge of these mechanisms and development of innovative tools to counteract them could result in new strategies to combat antimicrobial resistance."
Source: American Society for Microbiology
Dear Helpdesk: Working in a Toxic Health Care Environment
March 28th 2024Dear Helpdesk is your steadfast companion, offering life coaching and workplace advice from 2 seasoned IPs for some of your most challenging real-life situations. Let us help you navigate the intersection between work and life, guiding you to navigate the dynamic world of infection prevention with confidence and grace. This article is on handling a toxic health care environment.
Product Locator: Spring and Early Mother's Day Gift Guide for Infection Prevention Personnel
March 27th 2024Whether it's a spring holiday, birthdays, or no reason at all, infection prevention personnel love to give and receive gifts that help at the end of a stressful day. Infection Control Today® offers some gift ideas for infection prevention personnel and their families.
Catching Up With Vangie Dennis, AORN 2022-2023 President at AORN 2024
March 26th 2024Infection Control Today (ICT) had the privilege of catching up with Vangie Dennis, MSN, RN, CNOR, CMLSO, at the Association of periOperative Registered Nurses' (AORN’s) International Surgical Conference & Expo 2024. As the former president of AORN and an esteemed figure in perioperative services, Vangie Dennis shared insights into her recent endeavors and the exciting new chapter she's embarked upon.
How To Optimize Your Time Management Strategies for the Busy Infection Preventionist
March 25th 2024Is your calendar resembling a chaotic masterpiece of overlapping tasks? Join the club of infection preventionists striving to balance responsibilities. Dive into proven strategies from a fellow infection preventionist to reclaim control of your time, streamline tasks, and boost productivity effectively. This is an IP Lifeline article.