How Does Salmonella Get Into Eggs?

These white eggs could soon have a trace code on them. . (Photo: Reginaldo Bianco/Shutterstock)

More than 200 million eggs processed at Rose Acre Farms in Seymour, Indiana, were recently recalled for possible salmonella contamination. Those eggs were shipped to Colorado, Florida, New Jersey, New York, North Carolina, Pennsylvania, South Carolina, Virginia and West Virginia and sold to retail stores and restaurants, including Waffle House, according to USA Today. So far, 22 reports of illness on the East Coast have been reported.

The brand names on egg cartons to look for are Country Daybreak, Crystal Farms, Coburn Farms, Sunshine Farms, Glenview, Great Value, Walmart and Food Lion. The recall page from the U.S. Food and Drug Administration says cartons subject to the recall from those brands will have a plant number of P-1065 and a "Julian date range of 011 through 102 printed on either side of the carton or package."

If you bought those eggs, stop using them and return them to the place of purchase for a full refund.

How are eggs infected?

hen, eggs
Hens infected with salmonella can lay contaminated eggs. (Photo: Chokniti Khongchum/Shutterstock)

It may seem that since the inside of an egg is protected by a shell that the whites and the yolk would be protected from salmonella, but contamination usually happens before the shell forms. It occurs when a hen's ovary or oviduct are infected with the salmonella. The bacteria, explains University of Minnesota Extension, is present "before the shell forms around the yolk and white." Hens that are infected with salmonella do not get sick, so there's no way to tell if a chicken is infected.

Salmonella in eggs can be killed if eggs are pasteurized, but in the United States, eggs are not routinely pasteurized.

In some cases, the egg shells can be contaminated with fecal matter, reports Live Science. The bacteria may be present in the intestines and feces of the chicken and can be transferred to the eggs when the chickens sit on them.

Strict cleaning and inspection procedures were put into place in the 1970s to decrease this type of contamination.

Symptoms of salmonella poisoning

stomach cramps
Stomach cramps could be a sign of salmonella poisoning. (Photo: CHAjAMP/Shutterstock)

The Centers for Disease Control and Prevention (CDC) says symptoms of salmonella poisoning begin to occur within six to 48 hours after consuming food infected with the bacteria. Symptoms include diarrhea, vomiting, dehydration, fever and abdominal cramps. The illness can last 4 to 7 days. Most people recover fully without antibiotics or hospitalization. For older adults, infants and those with a compromised immune system, salmonella poisoning can be very serious and even life-threatening. Those people should see a doctor if salmonella poisoning is suspected.

The CDC also recommends seeing a doctor if you have:

  • A high fever over 101.5 degrees F
  • Diarrhea for more than 3 days that is not improving
  • Bloody stools
  • Prolonged vomiting that prevents you from keeping liquids down
  • Signs of severe dehydration such as making very little urine, dry mouth and throat, and dizziness when standing up

Preventing salmonella poisoning

cracking raw egg
Raw eggs can contain salmonella so handle them carefully. (Photo: Onion_Slimer/Shutterstock)

Purchasing pasteurized eggs would be the best way to prevent salmonella poisoning from eggs, but not all stores sell them. The taste and texture change during pasteurization so not everyone wants to use pasteurized eggs.

When working with unpasteurized eggs, follow these CDC-recommended tips to help prevent salmonella poisoning.

  • Buy eggs that have been kept refrigerated and refrigerate at home at 40 degrees F or colder.
  • Throw away dirty or cracked eggs.
  • Cook eggs to an internal temperature of 160 degrees F or higher and make sure the yolk and white are both firm.
  • Dishes made with raw or partially raw eggs should be made with pasteurized eggs.
  • Egg dishes should be eaten or refrigerated promptly after cooking. Eggs or foods made with eggs kept warm or at room temperature for over two hours should be discarded, one hour if the temperature is 90 degrees F or higher.
  • After handling raw eggs wash your hands, countertops, utensils, dishes and cutting boards with soap and water.