By Eryn Brown 6:31 PM EST, December 10, 2012 Scientists said
Sunday that the Clostridium difficile epidemic from 2002 to 2006
— an outbreak of gastrointestinal illness that spanned hospitals
across the globe — was caused by two closely-related strains of
the bacterium and not one, as had been previously believed.
Trevor Lawley of the Wellcome Trust Sanger Institute in Hinxton,
England and coauthors from other institutions sequenced the
genomes of C. difficile samples collected between 1985 and 2010,
mainly from hospital patients. Analyzing the samples, they found
the two lineages of the bacterium,which they named FQR1 and
FQR2. Both strains originated in North America and developed the
same mutation independently to become resistant to the
antibiotic fluoroquinolone (which until that period had been an
effective treatment for C. difficile infection). This acquired
resistance to the drug may have helped the bacterias’ spores
spread over vast geographic distances, the team wrote
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