A new "Frontline" documentary on PBS investigates the spread of dangerous pathogens in meat - particularly poultry - and why the food safety system isn't stopping the threat.

"The Trouble With Chicken" focuses on a 2013 outbreak of salmonella at one of the nation's largest poultry processors and reveals how contaminants are evading regulators and causing more severe illnesses as Americans consume more chicken than ever.

David Hoffman, a correspondent with "Frontline" who led the investigation, said on "Happening Now" that not only are one in four pieces of raw chicken in the U.S. infected with salmonella, the government wasn't even checking until recently.

Hoffman revealed that a million people are sickened by salmonella in the U.S. every year, with 19,000 hospitalized and more than 380 killed.

"The government's been aware for years that this is a big problem of foodborne illness," Hoffman said. "It's a public health problem."

"This chicken in the outbreak that's the subject of our film was sold on the West Coast for more than a year. There was no recall for more than 15 months," Hoffman said. "This wasn't a one-off thing. It kept happening over and over and over again."

Why isn't the government doing more about it? Jon Scott asked.

Hoffman said the government answered that they didn't feel that they had the authority and there were legal problems. They also have to have a "perfect gold standard" for evidence, requiring three different kinds of evidence before they will take action.

Watch more from "Happening Now" above and check out "The Trouble With Chicken."

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