Emergence of pan-resistance in KPC-2 carbapenemase-producing Klebsiella pneumoniae in Crete, Greece: a close call.

OBJECTIVES: KPC-2-producing Klebsiella pneumoniae (KPC-KP) ST258 has been rapidly expanding and is often associated with serious nosocomial infections. Last-line antibiotics such as colistin and tigecycline often remain the only treatment option. We describe here the evolving genetic background of KPC-KP isolates in Crete, Greece. METHODS: We tested the antibiotic susceptibility of 34 clinical isolates from patients hospitalized in 2010 and 2013-14. Whole-genome sequences of these isolates were analysed for acquired resistance genes and gene mutations. RESULTS: All KPC-KP isolates belonged to ST258 with the exception of one ST147 isolate. From 2014, 26% of isolates were non-susceptible to all antibiotics, compared with 0 of 11 isolates from 2010. Colistin resistance was associated with mutations in mgrB, which was present in 61% of isolates from 2014. Core-genome MLST analysis showed that pan-resistant isolates were closely related and appeared in two separate clusters. CONCLUSIONS: KPC-KP is rapidly evolving to pan-resistance in Crete. We identified molecular resistance markers for pan-resistant isolates and showed that core-genome MLST is a promising tool for molecular fingerprinting of KPC-KP ST258.

A waterborne Campylobacter jejuni outbreak on a Greek island.

A case-control and a case-crossover study were performed to investigate a Campylobacter jejuni outbreak in Crete in 2009. Most cases originated from rural areas, served by a different water-supply system from that of the adjacent town. Thirty-seven cases and 79 controls were interviewed; cases were interviewed for two different time periods for the case-crossover study. Stool cultures, PFGE and MLST subtyping were run in human samples. Univariately, consumption of tap water was associated with C. jejuni infection. Stratified analysis revealed that water-supply system was an effect modifier of this association. In the multivariable analysis, the rural areas' water supplier and drinking tap water were risk factors. No risk factors were revealed in the case-crossover study. No Campylobacter were isolated in the tested water samples. There is strong epidemiological evidence that tap water was the vehicle of the outbreak.