biostudies-literatureUnknown9(5)Hetland MAKWestern Norway Regional Health AuthorityTrond Mohn stiftelse<i>Klebsiella pneumoniae</i> sequence type (ST) 17 is a global problem clone that causes multidrug-resistant (MDR) hospital infections worldwide. In 2008-2009, an outbreak of MDR ST17 occurred at a neonatal intensive care unit (NICU) in Stavanger, Norway. Fifty-seven children were colonized. We observed intestinal persistence of ST17 in all of the children for up to two years after hospital discharge. Here, we investigated the within-host evolution of ST17 in 45 of those children during long-term colonization and compared the outbreak with 254 global strains. Ninety-two outbreak-related isolates were whole-genome sequenced. They had capsule locus KL25, O locus O5 and carried yersiniabactin. During within-host colonization ST17 remained stable with few single nucleotide polymorphisms, no acMicrobial genomicshttps://www.ebi.ac.uk/biostudies/studies/S-EPMC10272876biostudies-literatureWithin-patient and global evolutionary dynamics of <i>Klebsiella pneumoniae</i> ST17.PMC10272876F-12508TMS2019TMT03Rettedal SIKaspersen HLohr IHBakksjo RJHetland MAKHolt KEBernhoff ESundsfjord AHawkey JfalseWithin-patient and global evolutionary dynamics of <i>Klebsiella pneumoniae</i> ST17.<i>Klebsiella pneumoniae</i> sequence type (ST) 17 is a global problem clone that causes multidrug-resistant (MDR) hospital infections worldwide. In 2008-2009, an outbreak of MDR ST17 occurred at a neonatal intensive care unit (NICU) in Stavanger, Norway. Fifty-seven children were colonized. We observed intestinal persistence of ST17 in all of the children for up to two years after hospital discharge. Here, we investigated the within-host evolution of ST17 in 45 of those children during long-term colonization and compared the outbreak with 254 global strains. Ninety-two outbreak-related isolates were whole-genome sequenced. They had capsule locus KL25, O locus O5 and carried yersiniabactin. During within-host colonization ST17 remained stable with few single nucleotide polymorphisms, no ac2023-01-01T00:00:00Z2023 May2026-04-29T02:31:04.854Z2025-02-19T04:01:35.852ZS-EPMC102728763720006610.1099/mgen.0.001005