Cast your minds back a few months ago, to when the director of the US Centers for Disease Control and Prevention announced, “We have a very serious problem” with “nightmare bacteria,” and the chief medical officer of the United Kingdom backed him up a few days later, describing a “ticking time bomb” that threatens national security as seriously as terrorism.
Both public health chiefs were talking about a form of antibiotic resistance that is relatively new, and has suddenly emerged as much more serious — yet that the general public, and even much of the medical establishment, knows relatively little about. The acronym for this resistance is CRE, for carbapenem-resistant Enterobacteriaceae; breaking it down, that’s a family of gut-dwelling bacteria, a very common cause of hospital infections, that no longer respond to a group of last-ditch antibiotics called carbapenems.
Because they are effectively untreatable, CREs are very serious — as many as half of the patients who contract these infections die from them — and they are surprisingly common. In the United States, they have been found in 42 states to this point, in more than 4 percent of all hospitals, and more than 18 percent of “long term acute care” institutions, which offer critical care such as ventilator support for patients who need that level of care for months.
When Dr. Tom Frieden of the CDC and Professor Dame Sally Davies of the UK made their announcements in March — in language that (I suspect) was intended to jar people out of complacency about the future unreliability of antibiotics — a fairly common reaction among my readers was, “How on earth did this happen?”
It seemed a reasonable question.
This week, with the help of excellent editors at the journal Nature, I’ve tried to provide an answer. In a 3,000-word piece, I trace the emergence and spread of CREs from their first sighting by the CDC in a sample from 1996. The story is told in episodes extracted from the chronology of CREs’ rampage around the globe; from each episode, we’ve tried to extract a vital lesson. Among them:
When carbapenem resistance was first sighted — by chance, in a small surveillance program — there was no federal funding or political will to expand surveillance to see if the problem was occurring widely.
When the problem came to notice again — several years later and hundreds of miles away — the automated testing systems medicine uses to detect resistance had not been tuned to this new threat.
Once hospitals realized how persistent these resistant bugs were in the hospital environment, they took steps to corral patients and rigorously clean rooms — but they could do nothing to prevent the spread of these same bugs within the nursing homes and long-term care institutions from which they accept patients, undermining all their protective care.
When it became recognized that these highly resistant bacteria could travel asymptomatically in the guts of unknowing patients, not enough thought was given to how far they might spread, and so CREs disseminated across the globe.
There’s much more, and I hope you’ll take a look. If you can’t spare the time, you can get the tl;dr in the first 5 minutes of Nature‘s weekly podcast.
Here are some early readers’ reactions: