A Clinically-Oriented Antimicrobial Resistance Surveillance Network 2 (ACORN2): Results from three hospitals in Vietnam

OBJECTIVES: ACORN (A Clinically-Oriented Antimicrobial Resistance Surveillance Network) integrates antimicrobial resistance (AMR) surveillance with clinical data in hospitals across low- and middle-income countries. We describe ACORN2 data from Vietnam and compare findings with existing national surveillance data. METHODS: Hospitalized patients receiving intravenous antibiotics were enrolled from selected wards in three national hospitals. Infections were classified as community-acquired (CAI), healthcare-associated (HCAI), or hospital-acquired (HAI). Microbiological data were deduplicated to the first isolate of each bacterial species per sample types within each infection episode. Pathogen distribution and resistance patterns were analyzed by hospital, infection origin, and sample type. RESULTS: Among 5449 infection episodes, 2817 were CAI, 1615 HCAI, and 1017 HAI. Escherichia coli and Staphylococcus aureus predominated in sterile samples, while Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae were most frequent in non-sterile samples. A. baumannii and P. aeruginosa were common in HCAI and HAI. Resistance to third-generation cephalosporins and carbapenems was markedly higher in HCAI and HAI than CAI, with widespread carbapenem resistance in A. baumannii. Overall AMR levels exceeded those reported in previous national surveillance data. CONCLUSION: ACORN2 demonstrates a high burden of AMR in Vietnam, particularly in healthcare- and hospital-acquired infections, underscoring the value of clinically oriented surveillance to inform treatment and stewardship policies.