Emergence and Molecular Evolution of Carbapenem-Resistant Hypervirulent ST23 Klebsiella pneumoniae: The Superbug Phenomenon in China

Carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKP) ST23 has emerged as a significant global health threat. This study focuses on recent developments in China, where 120 ST23 CR-hvKP isolates have been identified. The earliest isolate was detected in Zhejiang in 2013, carrying the blaKPC-2 gene along with key virulence genes like rmpA, rmpA2, iro, and iuc. Among 119 isolates with regional data, Hebei had the highest percentage at 25.2%, followed by Jiangxi at 22.7%. KPC was the most common carbapenemase type, followed by NDM. NDM-producing strains are mainly found in northern provinces, while KPC-producing strains are more common in the south, contrasting with Europe's higher frequency of OXA-48.