An outbreak of salmonella at a pork processing plant in Washington highlights the importance of proper food safety.

An ongoing investigation into meat contaminated with drug-resistant bacteria has confirmed 152 people have been sickened.

The U.S. Centers for Disease Control and Prevention (CDC) reports that as of Aug. 27, 24 of those people infected with a strain of salmonella have been hospitalized, but no deaths have been reported.

The outbreak has been connected to whole pigs for barbecue and “fabricated pork products,” including offal, pork blood, and pork trim, that were produced from April 18 to Aug. 26 at Kapowsin Meats in Graham, Washington.

Following the discovery, Kapowsin initiated a recall of 523,380 pounds of suspected products that were sold around Washington.

The particular strain involved is Salmonella enterica Serotype 4,[5],12:i:-, which has been increasingly prevalent in human cases since the mid-1990s.

Using samples from 10 infected Washington pork eaters, a specialized CDC lab determined all of the isolates had developed resistance to the antibiotics ampicillin, streptomycin, sulfisoxazole, and tetracycline.

This type of resistance is not uncommon in modern farming as antibiotics are often routinely given to animals to promote growth and prevent disease. One study of 36 different flocks of broiler chickens in Canada found 64 percent of salmonella samples taken from the birds were resistant to one or more antimicrobials.

“Contaminated pork, especially with multidrug resistant salmonella, presents a serious problem to consumers,” Carmen Cordova, Ph.D., a microbiologist with the Natural Resources Defense Council, told Healthline. “Salmonella can be present already in an animal at slaughter and more contamination can occur as the meat is being processed.”

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