Genomic epidemiology and antifungal-resistant characterization ofCandida auris, Colombia, 2016-2021

Abstract

ABSTRACTSince 2016 in Colombia, ongoing transmission ofCandida aurishas been reported in multiple cities. Here, we provide an updated description ofC. aurisgenomic epidemiology and the dynamics of antifungal resistance in Colombia. We sequenced 99 isolates fromC. auriscases with collection dates ranging from June 2016 to January 2021; the resulting sequences coupled with 103 previously generated sequences fromC. auriscases were described in a phylogenetic analysis.AllC. auriscases were of clade IV. Of the 182 isolates with antifungal susceptibility data, 67 (37%) were resistant to fluconazole, and 39 (21%) were resistant to amphotericin B. Isolates predominately clustered by country except for 16 isolates from Bogotá, Colombia, which grouped with isolates from Venezuela. The largest cluster (N=166 isolates) contained two subgroups. The first subgroup contained 26 isolates, mainly from César; of these 85% (N=22) were resistant to fluconazole. The second subgroup consisted of 47 isolates from the north coast; of these, 81% (N=38) were resistant to amphotericin B.Mutations in theERG11andTAC1Bgenes were identified in fluconazole-resistant isolates, and two amino acid substitutions in PSK76257-(FLO8) and PSK74852 genes were associated with higher minimum inhibitory concentration values for amphotericin B. This work may help identify mechanisms conferring azole and amphotericin B resistance inC. auris.Overall,C. auriscases from different geographic locations in Colombia exhibited high genetic relatedness, suggesting continued transmission between cities since 2016. These findings also suggest a lack of or minimal introductions of different clades ofC. aurisinto Colombia.IMPORTANCECandida aurisis an emerging fungus that presents a serious global health threat and has caused multiple outbreaks in Colombia. This work discusses the likelihood of introductions and local transmission ofC. aurisand provides an updated description of the molecular mechanisms associated with antifungal resistance in Colombia. Efforts like this tracking genomic variation provide information about the evolvingC. aurisburden that could help guide public health strategies to controlC. aurisspread.