The
world is facing a possible post-antibiotic era, according to scientists
who have discovered bacteria that is resistant to all antibiotics —
including a last-resort drug. (Getty Images)
The new findings were published in the journal the Lancet Infectious Diseases.
During a routine surveillance of antibiotic resistance in China,
scientists discovered that a new bacterial genetic resistance mechanism
called MCR-1 prevents the drug colistin from killing bacteria. (Colistin
is often seen as a “last-resort” antibiotic when others aren’t
effective.)
Researchers
discovered that one-fifth of the animals they tested and 16 humans
carried MCR-1, as well as 15 percent of raw meat samples.
“The emergence of MCR-1 heralds the breach of the last group of antibiotics,” researchers wrote in the paper.
While
the findings are scary, they aren’t shocking, infectious disease
specialist Amesh A. Adalja, MD, an assistant professor at the University
of Pittsburgh Medical Center, tells Yahoo Health.
“Antibiotic
resistance is a steady march that’s been going on for a long time,” he
says. However, he says, bacteria are always going to become resistant to
our antibiotics — it’s just what they do.
Antibiotic
resistance is a blanket term that means a type of bacteria is resistant
to a particular type of drugs. “It can mean being resistant to one,
three, or all forms of antibiotics,” explains Adalja.
William
Schaffner, MD, an infectious disease specialist and professor at the
Vanderbilt University School of Medicine, explains the problem to Yahoo
Health this way: There are many millions of bacteria out there and they
multiply rapidly. As they multiply, some genetic mutations occur that
make them resistant to the antibiotic in use. The antibiotic will kill
off all the susceptible bacteria, but will leave behind the resistant
ones. They will grow and can spread to other people, becoming dominant.
That increases the odds another person will become infected with
antibiotic-resistant bacteria.
The
news about MCR-1 is particularly worrisome, because it breaches our
last line of defense: When doctors can’t kill bacteria with major forms
of antibiotics like penicillin and tetracycline, they might turn to
colistin.
“When
we see a hint that colistin-resistant bacteria are out there, it
becomes alarming because we don’t have very many new drugs,” says
Adalja.
Colistin
is often seen as a backup, he explains, because it can have serious
side effects such as kidney or nerve damage. “Even though we don’t like
to use colistin, it’s good to know that it’s there,” Adalja says.
While
some antibiotic resistance is inevitable, Schaffner says we can do
something about it. On an individual level, he urges people to use
antibiotics only when they’re needed, and only for the amount of time
that they’re prescribed. “Patients need to be aware that colds are viral
infections and will not be benefited by antibiotics,” he says.
Antibiotic
use in the raising of livestock is also contributing to the problem,
Schaffner says. While many companies are phasing out this practice due
to consumer demand, you can do your part by only purchasing meat that is
labeled “antibiotic free” or “raised without antibiotics."MCR-1 has currently been found only in China, but some researchers say it’s just a matter of time before it spreads. “Although currently confined to China, MCR-1 is likely to emulate other global resistance mechanisms,” the Lancet study claims. “Our findings emphasize the urgent need for coordinated global action.”
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