"It's scary, I mean, you just can't describe it really," said Bill Reeves.
Two years ago, 46-year-old Bill Reeves, who worked at a poultry processing plant in Batesville, Arkansas, developed a lump under his right eye.
"It went from about the size of a mosquito bite to about the size of a grapefruit," he said.
CBS Evening News anchor Katie Couric reports doctors tried several drugs that usually work on this potentially deadly infection: methicillin resistant staph or MRSA - before one saved his life.
"You go from a just regular day to knowing you may die in a couple of hours," Reeves said.
He wasn't the only worker from this farming community to get sick. Joyce Long worked at the hatchery, handling eggs and chicks. She got MRSA at least a dozen times, and had to try several drugs as well.
"It was real painful. Shots don't help, because it's so infected, it don't help much," she said.
Within weeks, 37 people at the hatchery got sick. They've filed personal injury claims against the company, Pilgrims Pride, which has no comment.
This is not an isolated incident and chickens aren't the only concern. A University of Iowa studylast year, found a new strain of MRSA -- in nearly three-quarters of hogs (70 percent), and nearly two-thirds of the workers (64 percent) -- on several farms in Iowa and Western Illinois. All of them use antibiotics, routinely. On antibiotic-free farms no MRSA was found.
Health officials are concerned if workers who handle animals are getting sick - what about the rest of us? Drug resistant infections have sky-rocketed over the past two decades, killing an estimated 70,000 Americans last year alone. It's an emerging health crisis that scientists say is caused not only by the overuse of antibiotics in humans, but in livestock as well. Antibiotics fed to healthy animals to promote growth and prevent disease.
"My fear is that one of these days we are going to have an organism that's resistant to everything that we know, and we'll be left powerless," said Thomas Cummins, Batesville's chief medical officer.
"There are a lot of concerns about antibiotics being added to animal feeds that may be contributing to MRSA as well as other antibiotic resistance," Cummins said. "Certainly the more bacteria are exposed to antibiotics in any shape or form, the more tendency there is for resistance."
There are different types of drug-resistant bacteria. Some, like e coli and salmonella, can be passed on to people by consuming undercooked meat and poultry. Now, scientists are worried that Americans may be acquiring drug-resistant MRSA - not from eating, but from handling tainted meat from animals that were given antibiotics.
Evidence of MRSA has been found in the nation's meat supply. But it's unclear how widespread it may be, because only a small fraction is tested for MRSA.
Shelley Hearnehas studied the health effects of factory farming for 25 years.
Pew Campaign On Human Health and Industrial Farming
"How does this go from the farm to the meat counter, to having an adverse effect on humans," Couric asked.
"If the bacteria becomes resistant to antibiotics, it can actually spread in many ways," Hearne said. "It could be in the food supply, but it also can be in waters that runoff in a farm. It could be in the air. It can happen very quickly in many different ways. It's why it's a practice that has to stop on the farms."
That practice occurs inside factory farms, where antibiotics help animals absorb and process food so they grow bigger, faster - a selling point pushed by the pharmaceutical industry. Because animals are packed into confinement pens, antibiotics are also used to keep disease from spreading like wildfire.
Liz Wagstrom is a veterinarian with the National Pork Board.
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"Some people say giving animals antibiotics to prevent illness or promote growth is like putting antibiotics in a child's cereal," Couric said. "You know, save them so they'll work when they are needed."
"I'd say we do strategically place them," Wagstrom replied. "It's not an all day, every pig gets antibiotics every day of his life."
"So you don't think they're being overused by farmers anywhere in this country," Couric asked.
Wagstrom replied, "the vast majority of producers use them appropriately."
But drug distributers and dozens of farm workers in four farm belt states -Iowa, Missouri, Arkansas, and Oklahoma - told us antibiotic use to promote growth is widespread on factory farms.
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Former hog worker, Kim Howland took CBS News inside a factory farm in Oklahoma where she worked two years ago.
"They administer drugs, you know, constantly, constantly, constantly," Howland said. "That's their fix for everything.
She said drugs like Tylan, Keflex, and Baytril, the same classes used to treat everything from skin to respiratory infections in humans - were given regularly to pigs that were not sick.
Her husband contracted MRSA and almost died.
"My conclusion was that I had carried it home," she said.
Dave Kronlage of Dyersville, Iowa says he uses antibiotics to accelerate growth and fend off disease. But, he says, he does so responsibly.
"You never worry about giving them antibiotics and having them develop bacterial disease that may be some sort of superbug for these animals," Couric asked.
"No. No," Kronlage replied.
"How do you prevent that from happening," Couric asked.
"We don't always use the same antibiotics for one thing," Kronlage replied.
Antibiotics, he says, keep the cost of meat at the supermarket lower - and his profits higher.
"Why do you think antibiotics are so necessary for your bottom line," Couric asked.
"Well, because the bottom line is how healthy you keep those pigs," Kronlage said. "The healthier those pigs are -- the bottom line looks better."
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But the bottom line on antibiotic use in factory farming is this: no one is really monitoring it.
Joshua Sharfstein,is the deputy director of the FDA.
"We want to put in place measures to reduce inappropriate use and we want to see that those are working - in order to do that we have to have a good surveillance system," Sharfstein said. "There's no question that needs to be improved."
"I loved hog farming. And I miss it. I wish I could go back," Kim Howland said. "But until the walls come down and the roofs come off, there's no chance."
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