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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Salmonella, which is often associated with undercooked chicken or eggs, is now being discovered more frequently in other types of meat.

The bacteria is found naturally in an animal’s gut. This includes humans.

The virus is spread most commonly though the slaughtering process or by exposure to feces. The bacteria can spread to vegetables when animal manure is used as a fertilizer.

The CDC reports an estimated 1.2 million illnesses per year in the United States.

While most cases result in symptoms similar to the stomach flu, such as nausea and diarrhea, a salmonella infection can be serious for people who aren’t healthy enough to fight off the bacteria, such as young children, older adults, and people with compromised immune systems.

Annually, those salmonella infections result in 19,000 hospitalizations and 450 deaths, according to the CDC.

All versions of drug-resistant bacteria (not just salmonella) cause an estimated 2 million illnesses and 23,000 deaths a year, the CDC states.

Recent cases of salmonella in the United States have been traced to frozen raw tuna used in sushi, frozen stuffed chicken entrees, and backyard chicken coops.

This February, a salmonella outbreak that occurred among parishioners of a North Carolina church was determined to come from smoked pork butt served at a conference.

The pork was reportedly cooked, chilled overnight and then recooked the next day. It sickened 57 people, according to Food Safety News.

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Salmonella, like most bacteria, can be killed with heat.

“To protect against the risk of contamination in the home, consumers should use a meat thermometer and prepare pork products according to recommended guidelines,” Cordova said.

Pork should be cooked to an internal temperature of 145 degrees, using the thermometer in the thickest part of the meat to ensure safety.

But besides cooking properly and practicing good sanitation, Cordova says consumers can protect themselves by choosing meats that were not raised with routine doses of antibiotics.

These products are often labeled “no antibiotics used” or “animal welfare approved,” which indicate the use of antibiotics only to treat illness.

“Consumers have a lot of power and are directly responsible for significant changes occurring in the marketplace on antibiotic use in meat production. Consumers can vote with their wallets and look for labels that make clear statements on antibiotic use,” Cordova said. “Consumers can also demand that their local grocery store carry pork from pigs raised without antibiotics.”

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