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Invasion of the Superbugs.

Drug-resistant bacteria are killing thousands of Americans every year. Can they be stopped?

One morning in 2011, Joseph Paz woke up with a pain in his right leg. A basketball and track-and-field athlete from Las Cruces, New Mexico, he chalked it up to a strain from cross country practice and took some painkillers. But the next day, the 16-year-old junior at Mayfield High School was in such agony that his mom drove him to the E.R.

Tests showed he had a bone infection in his left knee and a 2-foot blood clot in his right leg. He was diagnosed with MRSA (methicillin-resistant Staphylococcus aureus), an aggressive bacterium that causes deadly infections. Paz was hospitalized and given three antibiotics.

But the drugs didn't work. The infection quickly spread to his heart and, with his condition turning critical, he was transferred to El Paso, Texas, to undergo open-heart surgery.

"I was deathly afraid that this was going to kill him," says Joseph's aunt, Conchita Paz, who's a physician. "I know that MRSA can be deadly."

MRSA is one of the most lethal "superbugs" that are increasingly worrying scientists and health officials. Superbugs are a type of bacteria that can fight off the most powerful antibiotics that are supposed to destroy them. They can cause life-threatening blood infections, incurable cases of pneumonia, and flesh-eating diseases that can't be treated. They're growing in number and power, infecting more than 2 million Americans each year and killing at least 23,000--more than AIDS--according to the Centers for Disease Control and Prevention (CDC).

Recently, a superbug outbreak at a University of California hospital in Los Angeles contaminated almost 200 people and killed two. And last month, 32-year-old New York Giants tight end Daniel Fells was hospitalized and underwent seven surgeries because of a MRSA infection in his foot.

"We're in a crisis in the U.S.," says Helen Boucher, an infectious-disease specialist at Tufts Medical Center in Boston. "We face antibiotic-resistant infections every day."

And it's not just here in the U.S. Superbugs are infecting increasing numbers of people all over the world, killing an estimated 700,000 every year. In India alone, a superbug epidemic in 2013 killed almost 60,000 infants. The World Health Organization has called superbugs a "major global threat" that could have catastrophic effects (see "An Unstoppable Plague?" p. 11).

The Wonder Drug

How did superbugs get the upper hand over modern medicine? Blame it on the misuse and ovemse of antibiotics, experts say. To understand why, you have to go back more than a hundred years.

Until the 20th century, bacterial infections were the leading cause of death worldwide. Minor cuts or pimples that got infected routinely led to slow and painful deaths. Bacterial diseases like tuberculosis and meningitis--which attack organs from the lungs to the brain--were death sentences. The bubonic plague, caused by the bacterium Yersinia pestis, had killed more than 200 million people by the 1900s, including up to a third of Europe's population from 1347 to 1351, when it became known as the Black Death. The plague triggers horrible symptoms like fever, vomiting, and swollen lymph nodes filled with pus. There was little doctors could do: Amputations of infected limbs, ointments made from plants, and other treatments were rarely successful.

But everything changed one day in September 1928--and it happened by accident. Scottish scientist Alexander Fleming came back from a vacation and found that mold had grown on one of his bacteria-filled petri dishes in his lab in London. The mold had produced a substance, which he called penicillin, that had destroyed the bacteria. Penicillin eventually became the world's first antibiotic, and it made the world a safer place. Killer diseases could finally be treated. Life-saving procedures like surgeries to fix broken bones or failing kidneys became more common because antibiotics prevented killer infections that often followed surgery. Millions of lives were saved, and antibiotics became known as "the wonder drug."

By the 1950s, doctors were prescribing them to treat all kinds of sicknesses, even those not caused by bacteria. (Viral infections that cause colds, for example, don't respond to antibiotics.) Over time, better antibiotics were developed and their use expanded beyond people. Farmers began giving them to cows, pigs, and chickens to prevent, rather than treat, illness, and to make the animals grow larger for slaughter.

But the overuse of antibiotics has had a terrible side effect, which Fleming warned the world against when he accepted the Nobel Prize in Medicine in 1945: "It is not difficult to make microbes resistant to penicillin in the laboratory by exposing them to concentrations not sufficient to kill them, and the same thing has occasionally happened in the body," he said.

Bacteria are smart and extremely resilient. Every time they encounter an antibiotic, they "learn" a bit more about how to beat it. Over time, bacteria can grow resistant to drugs (see below): They build thick armors around their cells, develop scissor-like arms that can stop medicines, and even teach weak bacteria how to be strong.

"Bacteria have experienced and survived the dinosaurs," says Stuart Levy of the Center for Adaptation Genetics and Drug Resistance at Hifts University in Boston. "They win!"

Bacteria in Your Burger

Today, antibiotics are often prescribed for illnesses they can't cure. The CDC estimates that half of all antibiotics taken in the U.S. are unnecessary or used inappropriately. And an increasing amount of antibiotics is fed to livestock: Up to 80 percent of all antibiotics sold in the U.S. go to farm animals, not people.

The result is an increase in the number of superbugs that lurk in our homes, gyms, and even our food. A study by the U.S. government found that more than half of the ground turkey, pork chops, and ground beef collected from supermarkets contained resistant bacteria. Those pathogens can infect you if the meat isn't cooked properly. But that's not the only concern: If animal manure, which may contain resistant bacteria, is used as a fertilizer for crops, it can contaminate our water, fruits, and vegetables.

Superbugs were once a problem mainly in hospitals and nursing homes, preying on the sick and the elderly. But in the past decade, young, healthy people have increasingly become infected by superbugs. One of them was Jessica Petzold.

A 19-year-old from Sebastian, Florida, Petzold went to the doctor to treat a pimple on her chin one day in November 2014. She was given an antibiotic and sent home. But a few days later, Petzold developed a high fever and started complaining that her hip hurt. On November 20, she was hospitalized.

It turned out Petzold had contracted MRSA through the pimple. Within days, the infection spread to her lungs, her bloodstream, and her hip. The doctors prescribed more antibiotics, but just ten days after being admitted to the hospital, on Nov. 30, 2014, Petzold died.

One of the reasons the superbug problem has worsened is that no new class of antibiotics has been discovered since 1987, so bacteria have had time to grow resistant to currently available drugs. Most pharmaceutical companies have stopped working on new antibiotics because the research is costly and time-consuming: It can take a decade and as much as a billion dollars to get a new drug to market. Drug manufacturers prefer to invest in more-lucrative drugs that can treat diseases like cancer and diabetes--and that patients need to keep buying long-term. (Antibiotics are generally taken for about 10 days.)

"For years, we were able to stay ahead of the problem by developing new antibiotics," says William Schaffner, an infectious-disease specialist at Vanderbilt University in Nashville, Tennessee. But now we're not, he says. "The problem has become very, very serious."

New Drugs to the Rescue?

But the situation isn't hopeless. The CDC is trying to better track where superbug infections occur, so scientists can develop treatments more quickly. In March, the White House asked Congress for $1.2 billion to fight drug-resistant bacteria and reduce infections by 50 to 60 percent by 2020. The plan, which hasn't yet been approved, calls for coordinated federal and state efforts to curb the use of antibiotics on farms and in hospitals.

And a new drug was recently discovered by researchers at Northeastern University in Boston. The antibiotic, called teixobactin, has been tested in mice and cured severe infections, including MRSA, with no side effects. But it hasn't been tested in humans yet, and it doesn't work against some drug-resistant microbes. It could take five or six years for teixobactin to become available, if it turns out to be safe and effective for humans.

In the meantime, one of the best ways to fight superbugs is to prevent infection in the first place. The easiest way to do that? Wash hands regularly with soap for at least 30 seconds.

That's what Joseph Paz, who almost lost his life to MRSA, does. His open-heart surgery in El Paso, Texas, was just the beginning of his fight against the deadly infection in his body. A few days after the first surgery, he had to have a second one, which lasted six hours.

It took him a whole year of physiotherapy to get back on his feet and lead a relatively normal life again. Today, Paz, 20, is a junior at the University of New Mexico, where he studies chemical engineering. His MRSA infection left him with arthritis in his legs, and because of how damaged his left knee is, he had to give up running and basketball.

"[MRSA] turned my life upside down and backwards and sideways," Paz says. "I will never be the same."

A close-up of superbuq MRSA (yellow) killing a human immune cell

23,000

Number of people in the U.S. who die from drug-resistant bacterial infections every year. About 2 million are infected.

SOURCE: CDC

13

Average number of nights superbug-infected patients are hospitalized, compared with 6 for patients with nonresistant infections. With a superbug infection, you're twice as likely to die.

SOURCE: NATIONAL GEOGRAPHIC

How antibiotic resistance

1

When you get sick from bacteria, you take antibiotics, which kill the bacteria and make you feel better.

2

Over time some bacteria (colored red here) become resistant to antibiotics.

3

The drug-resistant bacteria multiply and take over.

4

Some bacteria even "teach" their drug resistance to other bacteria.

An Unstoppable Plague?

If left unchecked, by 2050 drug-resistant bacterial infections
could kill millions of people worldwide every year. Here's where
the deaths would likely occur, by continent.

North America            317,000
South America            392,000
Africa                 4,150,000
Europe                   390,000
Asia & Middle East     4,730,000
Oceania                   22,000

SOURCE: REVIEW ON ANTIMICROBIAL RESISTANCE, COMMISSIONED
BY THE U.K. GOVERNMENT IN 2014

Note: Table made from bar graph.
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Title Annotation:SCIENCE
Author:Potenza, Alessandra
Publication:New York Times Upfront
Date:Nov 23, 2015
Words:1794
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