The recent death of a woman in Reno, Nevada, from an infection resistant to every available kind of antibiotic in the U.S. highlights how serious the threat of antibiotic-resistant superbugs has become.
Experts say that while cases of bacteria resistant to all antibiotics are still extremely rare in the U.S., we should expect to see more in the future.
“This is an important case because it serves as a reminder to the health care community that these kinds of things can show up, even though they are rare,” said Randall Todd, director of epidemiology and public health preparedness at the Washoe County Health District, who co-wrote a study on this case. “We do have other forms of drug resistance, but this is the first time we’ve seen one that is pan-resistant, meaning there was nothing in the medicine cabinet available to treat this case.”
A woman in her 70s had just come back from a long visit to India when she was hospitalized on Aug. 18 and diagnosed with systemic inflammatory response syndrome: a fever, high heart rate, abnormal white blood cell count or an abnormal breathing rate in response to either an infection or some other trauma.
Before returning to the U.S., she had been hospitalized in India several times because she had fractured her femur and gotten an infection in the thigh bone and also her hip.
One week after she was admitted, the hospital confirmed her infection was caused by a carbapenem-resistant Enterobacteriaceae (CRE) called Klebsiella pneumoniae. Enterobacteriaceae is a kind of bacteria that can be a normal part of the human gut, but carbapenem-resistant ones don’t succumb to carbapenems — a class of antibiotics considered the last line of defense against bacterial infections.
Doctors reacted immediately to the identification of the CRE. In keeping with national guidelines, they dedicated a select few staff to treat her exclusively and instituted strict hand-washing protocol to keep the bug from spreading to other parts of the hospital. Thankfully, she was already in a single room.
In their search for a potential cure for her infection, doctors later found out that the cause was resistant to all 14 antibiotics the facility had to offer. Further testing at the U.S. Centers for Disease Control and Prevention confirmed that it was, in fact, resistant to all 26 antibiotics in the U.S.
The patient developed sepsis and died in early September.
The CDC published the details of this case Thursday and noted that there are three lessons to draw from her case.
The first thing they emphasized is that bacteria resistant to all available antimicrobials are very uncommon. Of the more than 250 carbapenem-resistant bacteria samples they have tested so far, 80 percent could be controlled with at least one aminoglycoside (another class of antibiotics) and 90 percent were susceptible to tigecycline, an antibiotic that is effective against drug-resistant bacteria.
The case also underscored the importance of infection control, as the bug posed a serious threat to other patients in the hospital. The study notes that the hospital tested all the other patients who were in the same unit and found that the CRE had not spread to them.
Finally, knowing that the woman had been hospitalized frequently in India gave her doctors much-needed insight on the infection she could be facing. Antibiotic-resistant bacteria are more common in other parts of the world, and knowing about international hospitalizations could give doctors clues into what they’re looking for, says Lei Chen, lead author of the report and the epidemiology program manager at Washoe County Health District in Nevada.
Chen was in close contact with the treating hospital throughout the case, and her department interviewed the woman’s household family members for any signs of illness. They were all healthy.
A ‘slowly dripping faucet’
One problem with superbugs is that there’s no way to know where they are within a healthy population, explains Tim Johnson, an antibiotic resistance expert at the University of Minnesota’s Veterinary School.
“These are what have been referred to as the silent killers, because it’s not like salmonella, where you ingest the salmonella and get sick,” Johnson said. “You can acquire these things, and they can hang out asymptomatically without causing disease for extended periods of time in your gut.”
He called the superbug issue a “slowly dripping faucet” that is going to leak more over time. In the meantime, the bottom line for U.S. doctors is that they should become more aware of the possibility that people can bring these superbugs back from different parts of the world.
“This is one of the first examples of a completely resistant bug,” Johnson concluded. “It’s definitely concerning — there’s no doubt about that. But it’s not something that we’re going to see rise dramatically.”
How to resist antibiotic resistance
We’ve known about the threat of pan-resistant bacteria for a long time but haven’t done enough to prepare, said David Weiss, director of the Emory Antibiotic Resistance Center in Atlanta. While the U.S. is taking encouraging steps to promote safe use of antibiotics, cut down on the use of antibiotics in livestock and invest in surveillance, the Nevada case demonstrates that this is a global problem that requires a global solution.
“One of the things that this case highlights is that people can pick up really nasty infections in other countries and then come home with them, so this is really a global problem,” Weiss said. “This isn’t a problem that we’ll be able to address just domestically.”
In America, about 2 million people a year are infected with bacteria resistant to some antimicrobial agent, and of those, 23,000 die of their infections. Antibiotic resistance is also a rising threat throughout the rest of the world. European analysts modeling a “worst-case scenario,” in which all microbes became resistant to medicine, estimated in 2014 that fatal superbug infections around the world could increase from 700,000 in 2014 to 10 million by 2050.
The World Health Organization launched a global action plan in November 2015 that involves raising awareness of antimicrobial resistance, investing in research and making sure that antimicrobial medicines are used properly. However, Johnson notes that antibiotic use in other parts of the world remain either unregulated or poorly regulated.
There are steps people can take to protect themselves. Antibiotic use causes antibiotic resistance, which is why it’s important for doctors to prescribe them only when they have confirmed the presence of a bacterial infection, not for a viral illness. Those who are prescribed antibiotics should take them exactly as instructed and not stop a course of treatment early, even though they might be feeling better.
Chen also advised patients to let their health care providers know if they’ve ever been hospitalized in another facility, state or country, and she said they should insist that doctors wash their hands before examining or touching them.
Outside of the health care facility, people can also protect themselves from antibiotic resistance by washing their hands regularly, staying up to date on vaccines, preparing and cooking foods safely, and using protection during sex to prevent the spread of infections.