Public health authorities are urging Americans to check their fridges and freezers after recalling more than 11 million pounds of ready-to-eat meat and poultry items over possible listeria contamination.

The Oklahoma-based company BrucePac, which sells pre-cooked proteins, is recalling 11,765,285 pounds of meat and poultry that it shipped to grocery stores, restaurants, schools and other institutions nationwide, according to the U.S. Department of Agriculture’s Food Safety and Inspection Service (FSIS).

The FSIS says it detected listeria during routine testing of finished products containing BrucePac poultry, which a subsequent investigation confirmed as the source.

The bacteria can cause a serious infection that is especially dangerous for people who are pregnant, over 65 or have weakened immune systems. There have been no confirmed reports of adverse reactions linked to the products, it adds.

Authorities first announced the recall last week, but have since expanded it to cover more than one million additional pounds of meat and poultry products. That amounts to hundreds of items from dozens of popular brands, sold at over a dozen grocery chains across the country.

The USDA also confirmed this week that the products have been distributed to schools and says it will post a school distribution list on its website once one is available.

The recalled products include salads, wraps, pasta bowls, burritos, enchiladas and many other ready-made frozen and family meals, and come from brands including Fresh Express, Rao’s, Boston Market, Atkins, Dole, ReadyMeals, Taylor Farms, Home Chef and Signature Select.

The stores that carry them include Aldi, Amazon Fresh, Giant Eagle, H-E-B, Kroger, Meijer, Publix, Target, Trader Joe’s, Walmart, Wegmans and 7-Eleven.

The affected goods were produced between May 31 and Oct, 8 and bear the establishment numbers “51205” or “P-51205” either inside or underneath the USDA mark of inspection. But BrucePac cautioned that the number is only on packages it ships directly to customers, not retail packages.

“Because we sell to other companies who resell, repackage, or use our products as ingredients in other foods, we do not have a list of retail products that contain our recalled items,” the company said in a statement, adding that the best way for people to identify contaminated products is through the USDA website or by calling the company or retailer from which they got the package.

The USDA is maintaining a list of recalled products — which is 345 pages long as of Wednesday — and urging people to use the search function to look up individual products, stores and brands and throw away any that they may have at home.

Authorities say they are also “concerned that some product may be available for use in restaurants, institutions, schools and other establishments” and are urging them to throw the goods out immediately.

For its part, BrucePac says it is working closely with the USDA to notify consumers, contact the food companies and distributors affected and ensure “all necessary actions are taken to ensure a safe food supply.”

“We will not resume production until we are confident the issue has been resolved,” it added.

What to do if you’re worried

The USDA is urging people to toss any affected products and monitor its website for more information as it becomes available.

It says consumers with food safety questions can call the toll-free USDA Meat and Poultry Hotline at 888-674-6854 or email MPHotline@usda.gov, and can report complaints about any meat, poultry or egg products online.

Anyone concerned about illness should contact their healthcare provider, the department adds.

Eating food contaminated with listeria can cause listeriosis, an invasive infection that spreads beyond the gastrointestinal tract and must be treated with antibiotics.

The Centers for Disease Control and Prevention says listeria infection is the third leading cause of death from foodborne illnesses in the U.S., estimating that 1,600 people are infected and 260 people die from it each year.

The infection can be fatal in older adults and people with weakened immune systems, and can cause miscarriages, stillbirths, premature delivery in pregnant women as well as life-threatening infections in their newborns.

Symptoms of listeriosis include fever, chills, muscle aches, nausea, diarrhea, stiff neck, loss of balance and convulsions. Symptoms could begin within a few days of eating contaminated food in some cases, but in others could take 30 days or more to show up, according to the Mayo Clinic.

The USDA says anyone in the higher-risk categories who experiences flu-like symptoms within two months after eating contaminated food should seek medical care and tell their health care provider about the food.

Listeria concerns have been responsible for other recalls in recent months, including an outbreak linked to Boar’s Head deli meat that resulted in 59 hospitalizations and 10 deaths across 19 states this summer. The USDA has since opened an internal investigation into its handling of prior reports of safety violations at Boar’s Head’s Virginia plant.

NPR’s Chandelis Duster contributed reporting.