Polyclonal Multidrug ESBL-Producing Klebsiella pneumoniae and Emergence of Susceptible Hypervirulent Klebsiella pneumoniae ST23 Isolates in Mozambique.

Globally, antibiotic-resistant Klebsiella spp. cause healthcare-associated infections with high mortality rates, and the rise of hypervirulent Klebsiella pneumoniae (hv Kp ) poses a significant threat to human health linked to community-acquired infections and increasing non-susceptibility. We investigated the phenotypic and genetic features of 36 Klebsiella isolates recovered from invasive infections at Hospital Central of Maputo in Mozambique during one year. The majority of the isolates displayed multidrug resistance (MDR) (29/36) to cephalosporins, gentamicin, ciprofloxacin, and trimethoprim-sulfamethoxazole but retained susceptibility to amikacin, carbapenems, and colistin. Most isolates were ESBLs-producing (28/36), predominantly carrying the bla CTX-M-15 and other beta-lactamase genes ( bla SHV , bla TEM-1 , and bla OXA-1 ). Among the 16 genomes sequenced, multiple resistance genes from different antibiotic classes were identified, with bla CTX-M-15 , mostly in the IS Ecp1 - bla CTX-M-15 - orf477 genetic environment, co-existing with bla TEM-1 and aac(3)-IIa in five isolates. Our results highlight the presence of polyclonal MDR ESBL-producing K. pneumoniae from eight sequence types (ST), mostly harbouring distinct yersiniabactin within the conjugative integrative element (ICE). Further, we identified susceptible hv Kp ST23, O1-K1-type isolates carrying yersiniabactin ( ybt1 /ICEKp10), colibactin, salmochelin, aerobactin, and hypermucoid locus ( rmpADC ), associated with severe infections in humans. These findings are worrying and underline the importance of implementing surveillance strategies to avoid the risk of the emergence of the most threatening MDR hv Kp .