Trends in pathogens and antimicrobial resistance in culture-proven neonatal sepsis over a decade (2015–2024): the impact of COVID-19 pandemic

Abstract

Background Neonatal sepsis remains a leading cause of mortality and long-term disability worldwide. The coronavirus disease 2019 (COVID-19) prevention measures effectively curbed viral transmission. However, evidence of their long-term impact on the pathogen spectrum and antimicrobial resistance in neonatal sepsis is limited. Methods In this single-center retrospective observational study at Henan Children’s Hospital, 894 neonates with culture-confirmed sepsis (2015–2024) were enrolled. Using pandemic policy time points, we divided the study into three phases and compared pathogen spectrum and antimicrobial resistance. Results Among neonates with sepsis, preterm proportion increased from 32.5% to 46.2%. The pathogen spectrum shifted from Gram-positive to Gram-negative predominance. Coagulase-negative staphylococci (CoNS) detection declined from 36.6% to 9.8%, a trend consistent across preterm/full-term and early-onset/late-onset subgroups. Klebsiella pneumoniae (K. pneumoniae) maintained high resistance to third-generation cephalosporins, while Escherichia coli (E. coli) showed a numerical increase in ceftazidime resistance. In contrast, CoNS and Enterococcus faecium (E. faecium) remained susceptible to vancomycin and linezolid. E. coli maintained favorable susceptibility to carbapenems and piperacillin-tazobactam, whereas K. pneumoniae showed a fluctuating carbapenem resistance trend that initially increased then declined, though it remained susceptible to tigecycline. All-cause mortality increased from 1.4% to 5.4%, with Gram-negative bacteria predominating in fatal cases. Conclusion Enhanced hand hygiene and contact isolation are consistent with a sustained decline in CoNS, but show limited association with changes in Gram-negative bacilli. Routine surveillance and optimized empirical therapy remain crucial for improving neonatal sepsis outcomes.