Data collected over a span of 15 years from the Veterans Affairs (VA) Healthcare System has provided a critical roadmap for antimicrobial resistance and infection prevention, according to a study published in The Lancet Infectious Diseases. This extensive analysis, carried out by researchers from the U.S., proved reductions in certain antibiotic-resistant healthcare-associated infections (HAIs) prior to the outbreak of COVID-19.
The researchers attributed this reduction, particularly in pathogens like methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium, to the successful implementation of infection control measures in the VA network. However, the study painted a mixed picture, also showing increased incidence of HAIs for varied pathogen-drug combinations throughout the research period. This troubling surge, accelerated during the early days of the COVID-19 pandemic, emphasized the need for continued and enhanced antimicrobial resistance surveillance.
The research team scrutinized electronic health records, analyzing clinical microbiology data from patients admitted to 138 VA medical centers over 15 years, from February 2007 to March 2022. They examined the resistance proportion and the phenotypic incidence rate, focusing on nine pathogens most commonly linked with HAIs, community-acquired infections, and multidrug-resistance, studied alongside 28 drug-pathogen combinations. Throughout the research timeframe, data was gathered from 991,527 incident isolates linked to 507,760 patients.
Most frequently isolated organisms were S aureus, Escherichia coli, and Klebsiella pneumoniae. Up until December 2019, infection incidence across all pathogens decreased, with most significant declines in Enterococcus faecium and S aureus. Furthermore, the proportion of MRSA and vancomycin-resistant E faecium infections also dropped. Despite this, not all pathogens exhibited a decrease in resistance during the pre-COVID era. For instance, third-generation cephalosporin resistance in E coli infections saw a notable increase.
The researchers also noted an alarming spike in instances of carbapenem-resistant Acinetobacter baumannii during the COVID-19 pandemic. The findings correlate with reports from the Centers for Disease Control and Prevention, documenting similar upward trends during the same period. The pre-pandemic dip in HAI incidence may be linked to specific trends and policies implemented within the VA Healthcare System. For instance, a decrease in fluoroquinolone resistance coincided with substantial reductions in fluoroquinolone use. This shift in usage habits can possibly be attributed to several fluoroquinolone safety warnings issued by the Food and Drug Administration.
The report concludes that the observations have vital implications for policy direction, clinical practice, and antimicrobial stewardship in health institutions across the U.S, echoing the necessity for system-wide infection prevention and antimicrobial stewardship programs. At the same time, it underscores the growing urgency for reinforced surveillance, and decisive action against ever-increasing antimicrobial resistance.