- Woman, 49, presented at Pennsylvanian clinic with a urinary infection
- Tests showed the sample was positive for a gene, known as mcr-1
- The gene is responsible for turning bacteria resistant to antibiotics
- Experts found the bacteria was resistant to colistin - a last line antibiotic
- CDC director Dr Tom Frieden says the discovery 'shows the end of the road isn't very far away for antibiotics'
A woman in Pennsylvania has become the first American to test positive for a strain of bacteria that is resistant to all antibiotics, even those used as the last line of defense.
The alarming discovery 'heralds the emergence of truly pan-drug resistant bacteria', experts have warned.
And US health officials added it could mean the 'end of the road' for antibiotics.
In a paper published in the journal Antimicrobial Agents and Chemotherapy, researchers from the Walter Reed Army 6 Institute of Research in Maryland revealed the bacteria was identified in the urine of a 49-year-old woman.
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| A 49-year-old woman from Pennsylvania, who presented with a urinary infection, tested positive for the mcr-1 gene, that causes bacteria to become resistant to all antibiotics, including colistin, the strongest of the drugs. Pictured, an illustration of E.coli, which can also become resistant, by the gene |
She presented at a clinic in Pennsylvania in April, with symptoms indicative of a urinary tract infection.
Their report highlights that 'to the best of our knowledge' this is the first report of the bacteria being detected in the US.
The researchers warned: 'The recent discovery of a plasmid-borne colistin resistance gene, heralds the emergence of truly pan-drug resistant bacteria'.
CDC director, Dr Tom Frieden, said: 'It basically shows us that the end of the road isn't very far away for antibiotics, that we may be in a situation where we have patients in our intensive-care units, or patients getting urinary tract infections for which we do not have antibiotics,' the Washington Post reported.
Colistin is the last antibiotic used to combat bacteria that are resistant to the strongest antibiotics.
The drug has remained the best tool available to treat multi-drug resistant bacteria, because bacteria were not exchanging genes that triggers resistance.
The latest discovery shows that colistin may be losing its effectiveness in antimicrobial therapy.
Researchers fear bacteria may now be exchanging resistance genes for the drug.
The alarm was first sounded in the microbiology community late last year, when the first transferrable gene for colistin-resistance was identified in China.
Since the report, the global health community has monitored and searched for the occurrence of the gene in the food supply and in humans.
Since then, the colistin-resistant gene has been reported in Europe and Canada, and now in the US.
The woman's urine sample was sent to the Walter Reed National Military Medical Center for testing.
---CDC director, Dr Tom Frieden
It basically shows us that the end of the road isn't very far away for antibiotics
The results showed no safe dosage of colistin would be effective to treat such a bacterial infection.
Researchers at the institute recognized colistin resistance and sent a sample to the Walter Reed Army Institute of Research for sequencing, which identified the colistin-resistant gene, mcr-1.
Dr Patrick McGann, said: 'Colistin is one of the last effcacious antibiotics for the treatment of highly resistant bacteria.
'The emergence of a transferable gene that confers resistance to this vital antibiotic is extremely disturbing.
'The discovery of this gene in the US is equally concerning, and continued surveillance to identify reservoirs of this gene within the military healthcare community and beyond is critical to prevent its spread.'
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CDC director, Dr Tom Frieden, said: 'It basically shows us that the end of the road isn't very far away for antibiotics, that we may be in a situation where we have patients in our intensive-care units, or patients getting urinary tract infections for which we do not have antibiotics' |
It has emerged the CDC and the US Department of Agriculture are also investigating a case of swine intestinal infection, with an E.coli strain bearing the mcr-1 gene.
While there is no evidence, officials stress, that the two recent findings are linked, the evidence of the strain in the US is a public health concern.
The gene is transferable to other bacteria, which could worsen the current global crisis of antibiotic resistance.
An urgent public health response is underway to contain and prevent potential spread of mcr-1, officials said.
Dr Gerry Wright, director of the Michael G.DeGroote Institute for Infectious Disease Research at McMaster University said while serious, the discovery of the strain in the US was to be expected.
He said: 'The mcr-1 gene has been reported across the globe since it was first reported in November of last year.
'The US was actually not an anomaly in not finding it until now/
'I expect it's been around for some time, just not detected.
'Because the patient has no reported travel history, you can predict with certainty that mcr-1 is established in the USA.'
This finding has been published by Antimicrobial Agents and Chemotherapy (AAC) of the American Society for Microbiology (ASM).