Listeria has grounded certain food services in recent days for some American Airlines and United Airlines flights.

Different foodservice providers are involved. In both cases, Listeria bacteria was found at food preparation areas.

The Gate Gourmet catering facility at LAX airport, which provides foods, beverages and related services to American Airlines and other carriers. Officials from the airline said Wednesday catering for American flights out of LAX would not be provided by Gate Gourmet for at least a week.

Flight attendants are urged to monitor themselves for symptoms of Listeria infection for the coming months. It can take up to 70 days after exposure for symptoms to develop.

“Although there are currently no known, or reported cases of listeriosis attributed to Gate Gourmet’s catering, there will be no further catering of AA flights from this facility continuing for at least a week. Gate Gourmet will still be providing some services such as the removal of trash as well as the provisioning of wet ice, drinks and some snacks,” according to a letter sent to flight attendants by the Association of Professional Flight Attendants on Wednesday.

The American Airlines announcement came two days after a United Airlines caterer in Denver suspended operations because inspectors found Listeria.

Journey Cuisine, a Denver-based food manufacturer, supplies prepared meals for grocery retailers as well as United Airlines flights out of Denver International Airport. The food company reported to United officials on Monday that the Listeria contamination was found Friday.

In a statement to local media in Denver, United Airlines officials said none of the food prepared for the airline had tested positive for Listeria. The airline is using other suppliers for food on its flights out of Denver and plans to return to normal operations in 10 to 15 days.

Journey Cuisine prepares about 9,000 meals a day for United Airlines and King Soopers grocery stores in the Denver area, according to Denver’s ABC News affiliate Channel 7. The grocery retailer, which is part of the Kroger Co., told Channel 7 it is transitioning away from using Journey Cuisine products.

Advice to travelers and consumers
Anyone who has recently eaten food on American Airlines flights out of LAX or United Airlines flights out of Denver International Airport and developed symptoms of Listeria infection should seek medical treatment and tell their doctors about the possible exposure to the bacteria.

Symptoms can include fever, severe headache, stiffness, nausea, abdominal pain and diarrhea, according to the Centers for Disease Control and Prevention. Listeria can cause serious and sometimes fatal infections in young children, frail or elderly people, and others with weakened immune systems, including cancer patients and organ transplant recipients.

It can take up to 70 days after exposure for listeriosis symptoms to develop, so anyone who has eaten food on the implicated airline flights or prepared meals at Denver area King Soopers grocery stores should monitor themselves for the coming weeks.

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