First-ever case of MCR-1 superbug reported in the US

The dreaded bug, known as MCR-1 (see Relevant Reports below), which is resistant to all known forms of medication, has been found in the US for the first time, igniting concerns over the dwindling effectiveness of antibiotics. The case involves a 49-year-old woman in Pennsylvania whose urinary tract infection tested positive for a strain of E.coli that is resistant to colistin, the antibiotic of last resort for such infections. As we noted, this 'superbug' was recently discovered in China, Canada, and Europe. Centers for Disease Control and Prevention Director Dr. Tom Frieden warns that while this may be the first case in the US, more superbugs should be expected; he has warned doctors against overusing antibiotics and has urged scientists to develop new drugs quickly. On another note, UK prime minister David Cameron has warned that failure to tackle antibiotic resistance will lead to "catastrophic consequences", and has committed his government to halving drug-resistant infections by 2020, including calling for a $1.6bn a year global fund to reward pharmaceutical companies that develop drugs to fight "superbugs".

Story highlights It is the first U.S. case of a bacterial infection that was resistant to an antibiotic of last resort The CDC director warns that we may see more of these cases Dr. Tom Frieden urges new drugs and encourages doctors to stop over-prescribing antibiotics

CNN —

A 49-year-old Pennsylvania woman showed the presence of a rare kind of E. coli infection, the first known case of its kind in the United States. It is a superbug that is resistant to many antibiotics, even Colistin, which doctors use as a last resort when other antibiotics fail.

The case was detailed in a report by the U.S. Department of Defense on Thursday. Centers for Disease Control and Prevention Director Dr. Tom Frieden talked about the case at the National Press Club in Washington.

The woman went to a clinic in Pennsylvania, and a sample was forwarded to Walter Reed National Military Medical Center. Walter Reed found the bacteria in her urine. There is no indication of how the bacteria got into the woman’s system. She had not traveled outside the United States within the past five months.

The CDC and the Pennsylvania Department of Health mobilized immediately to investigate the case and to trace contacts the patient may have had to see whether the bacteria had spread.

The woman was treated and released and has no other medical problems related to the bacteria that we know of, according to Dr. Alex Kallen, a medical officer with the CDC.

The CDC said it is looking for other potential cases in the health care facility the patient visited.

The bacteria have been identified in other infections outside the United States. Doctors saw cases in Europe, Canada and China.

The U.S. Department of Agriculture also found one strain of Colistin-resistant E. coli in a single sample of a pig intestine, according to a statement from the Department of Health and Human Services. The USDA is trying to determine what farm the pig came from to see whether any other animals were impacted.

These two cases are what the CDC characterized as a “warning sign, more than a catastrophe,” according to Kallen.

The concern is that traits of this rare mutant Colistin-resistent E. coli could jump to other bacteria that respond only to Colistin, creating a potentially unstoppable superbug.

One report suggests that antibiotic-resistant infections can result in the deaths of half the patients who become infected.

Antibiotic resistance has become a growing problem in this country. The World Health Organization has warned that it is one of the biggest threats to global health today.

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Frieden warned that although this is the first case in the United States, we should expect to see more such superbugs in the near future. Frieden, who often warns doctors against overuse of antibiotics, urged scientists to develop new drugs quickly.

Each year in the United States, at least 2 million people become infected with other kinds of bacteria that can’t be beaten with most antibiotics, and at least 23,000 people die each year as a result of those infections, according to the CDC.

“The medicine cabinet is empty for some patients,” Frieden said. “It is the end of the road unless we act urgently.”