Imagine a world where every forthcoming Star Wars movie was just like The Phantom Menace. And then they got worse. That kind of scenario is exactly what is happening with an antibiotic-resistant bacteria named after the infamous prequel, except instead of increasingly bad movies, the US is poised to see increasingly untreatable infections.
The so-called “superbug” in question is a strain of Carbapenem-resistant enterobacteriaceae, or CRE. “Carbapenem-resistant” means that this kind of enterobacteria–a family of bacteria that includes everything from Salmonella to E. coli –has gained resistance to the antibiotics that kill bacteria not susceptible to most other drugs. Carbapenems, then, are a last line of defense against the post-antibiotic apocalypse.
Back in 2012, a paper named a particularly nasty strain of CRE after The Phantom Menace. Maybe the authors thought the bacteria were a part of the worst strain of CREs they had ever seen, maybe they literally meant that the bacteria are an impeding doom we aren’t tracking closely enough. Probably the latter. “Unfortunately we foresee further and extensive spread (likely uncontrollable),” the authors write.
Last week, the CDC confirmed those fears, reporting that since 2010, 43 patients in the US have contracted this particular infection, up from just one in 2010. It doesn’t sound like much, but this strain has a 50 percent mortality rate, and has found away around our last line of defense drugs.
Bacteria usually gain resistance to our chemical weapons through evolution. Every time a bacteria reproduces, it has a chance to gain a gene that protects it from us. When you bombard someone’s body with an antibiotic, for example, most of the bacteria are wiped out. But those with evolved resistance linger, passing on its resistance genes to the next generation. Over time, bacteria can and do bypass the antibiotic obstacles we throw in their way.
It gets worse. Bacteria can also leapfrog evolution and transfer genes horizontally among themselves and their family of microbes–instead of being gifted to the next generation, resistance genes spread rapidly from microbe to microbe. The phantom menace strain does this with a tiny package of DNA, called a plasmid, that spreads a Carbapenems-destroying enzyme.
“What we’re seeing is an assault by the microbes on the last bastion of antibiotics,” said CDC Director Thomas Frieden in an interview.
Though the few cases in the US since 2010 do point to the spread of these jumping genes, it looks like the origin was elsewhere. “Although clusters…suggest transmission has occurred in the United States, the majority of identified patients were reported to have had exposure to health care outside the United States,” writes the CDC.
The phantom menace is spreading, and we have to remain vigilant against these asexually reproducing enemies. No one wants another attack of the clones.
Featured Image: Lucasfilm