One of the recalled pasta meal products.

The death toll has increased to six people in a multi-state listeria outbreak linked to ready-to-eat pasta products sold at stores such as Walmart, Kroger and Trader Joe's.

In an Oct. 30 update, the Food and Drug Administration (FDA) and Centers for Disease Control and Prevention (CDC) announced that the outbreak, which health agencies began investigating in June, has resulted in 27 confirmed listeria infections across 18 states, resulting in 25 hospitalizations, six deaths and one fetal loss.

The numbers are only the known cases and likely do not represent the full number of people sick, according to the CDC.

As an investigation into the outbreak continues, several major retailers, including Albertsons, Kroger, Walmart, Trader Joe's and Sprouts, have put out rolling notices recalling impacted products, advising consumers to check their fridges and freezers for any potential impacted foods.

See map of states with listeria cases in pasta outbreak

Cases of illness linked to the outbreak have been confirmed in 18 states as of Oct. 30. Deaths occurred in Hawaii, Illinois, Michigan, Oregon, Texas and Utah.

Recalled products and what to do with them

Ready-to-eat pasta products sold at grocery chains nationwide, many under different brand names, have been recalled in the outbreak. For a full list, check out USA TODAY's previous reporting.

Both the CDC and FDA advise returning affected products to the place of purchase for a refund or tossing them in the trash.

Wash and sanitize bowls, cups, storage containers and other surfaces that may have come into contact with the recalled products. Always thoroughly wash your hands after handling and preparing food, especially raw or uncooked products.

What are the symptoms of listeria poisoning?

Listeria poisoning is a foodborne bacterial infection most commonly caused by the bacterium Listeria monocytogenes, according to the CDC. It is considered a serious condition and can be dangerous or life-threatening, especially to older adults, people with weak immune systems and pregnant women.

Per the CDC, symptoms include:

  • Fever
  • Muscle aches
  • Headache
  • Stiff neck
  • Confusion
  • Loss of balance
  • Convulsions
  • Diarrhea
  • Other gastrointestinal symptoms
  • Miscarriage, stillbirth, premature delivery and/or life-threatening infection of newborn infants
  • Death

People in higher-risk categories who experience flu-like symptoms within two months of consuming contaminated food should seek medical attention, according to the CDC.

This article originally appeared on USA TODAY: Listeria outbreak tied to pasta meals sickens 27 people in 18 states. See map.

Reporting by Mary Walrath-Holdridge, USA TODAY / USA TODAY

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