Antimicrobial resistance prevalence in bloodstream infection in 29 European countries by age and sex: An observational study

This study aimed to quantify the variation in antimicrobial resistance prevalence and incidence of bloodstream infections (BSI) by age and sex across bacteria and antibiotics in Europe. Data was collected from routine surveillance between 2015 and 2019 on BSIs in 29 European countries from the European Antimicrobial Resistance Surveillance Network (EARS-Net). The study found distinct patterns in resistance prevalence by age, with trends often varying more within an antibiotic family than within a bacterial species. For methicillin-resistant Staphylococcus aureus (MRSA), age trends were mostly positive, with 72% of countries seeing an increased resistance between males aged 1 and 100 years and a greater change in resistance in males. Age trends for aminopenicillin resistance in E. coli were mostly negative, with a smaller change in resistance in females. The study highlights gaps in our understanding of AMR epidemiology and calls for future work to determine the drivers of these associations to more effectively target transmission and antibiotic stewardship interventions.