然后呢，其实他们干了什么事也不用我再来描述了=w=
Background Gram-negative Enterobacteriaceae with resistance to carbapenem conferred by New Delhi metallo-β-
lactamase 1 (NDM-1) are potentially a major global health problem. We investigated the prevalence of NDM-1, in
multidrug-resistant Enterobacteriaceae in India, Pakistan, and the UK.
Methods Enterobacteriaceae isolates were studied from two major centres in India—Chennai (south India),
Haryana (north India)—and those referred to the UK’s national reference laboratory. Antibiotic susceptibilities
were assessed, and the presence of the carbapenem resistance gene blaNDM-1 was established by PCR. Isolates were
typed by pulsed-field gel electrophoresis of XbaI-restricted genomic DNA. Plasmids were analysed by S1 nuclease
digestion and PCR typing. Case data for UK patients were reviewed for evidence of travel and recent admission to
hospitals in India or Pakistan.
Findings We identified 44 isolates with NDM-1 in Chennai, 26 in Haryana, 37 in the UK, and 73 in other sites in India
and Pakistan. NDM-1 was mostly found among Escherichia coli (36) and Klebsiella pneumoniae (111), which were highly
resistant to all antibiotics except to tigecycline and colistin. K pneumoniae isolates from Haryana were clonal but
NDM-1 producers from the UK and Chennai were clonally diverse. Most isolates carried the NDM-1 gene on plasmids:
those from UK and Chennai were readily transferable whereas those from Haryana were not conjugative. Many of the
UK NDM-1 positive patients had travelled to India or Pakistan within the past year, or had links with these countries.
Interpretation The potential of NDM-1 to be a worldwide public health problem is great, and co-ordinated international
surveillance is needed.
