At Health Talk, we’re big fans of infographics. We thought the one above, from Trevor Lawley and Nature Genetics was great.
The graphic (and it’s accompanying story) appeared this weekend on NPR’s Shots Blog and helps illustrate how a powerful infection, clostridium difficile (or C-diff. for short), traveled the world.
According to author Michaeleen Doucleff, around 10 years ago a particularly nasty and antibiotic-resistant strain of C-diff. appeared in the United States. Researchers started to wonder where it came from and how it had become so effective at combating our arsenal of antibiotics.
Well, after sequencing the DNA of more than 150 C-diff. strains found in patients between 1985 and 2010, scientists at the Wellcome Trust Sanger Institute might have found an answer.
According to Doucleff:
“From the DNA sequences, they calculated that the highly virulent form of C. difficile first appeared in Pittsburgh around 2001. From there, it spread to Oregon, New Jersey, Arizona and Maryland, where it caused major hospital outbreaks in each state. Since 2007, the drug-resistant bacteria have also made appearances in South Korea and Switzerland. The genomic data also showed that another superbug of C. difficile cropped up independently in the U.S. around the same time.”
As for how these strains became resistant to our antibiotics? Researchers at Wellcome think they found the answer to that too. Evidently both aforementioned strains of C-diff. underwent a single mutation – independently – that allowed them to fight off antibiotics commonly prescribed a decade prior. Scary stuff.
Check out Doucleff’s story at NPR for more.
P.S., if Doucleff’s story leaves you wanting to learn more about treatment options for C-diff. infections, be sure to check out our earlier post on the concept of fecal transplants.