Four patients have been infected by Listeria and one has died after eating potentially contaminated cheese at a hospital in Switzerland.

During an internal check, Käserei Vogel AG, based in Steinerberg, found Listeria in semi-hard cheese and at its production site. The company issued a recall and informed its buyers to remove the products from shelves.

One of the buyers is a supplier to the Center Hospitalier du Valais Romand (CHVR). This supplier told the CHVR purchasing manager on April 30 about the problem. He instructed the immediate withdrawal of implicated cheeses. The last delivery was April 8, but it has not been ruled out that previous lots were also contaminated.

Patients ate cheese but not known which brand
From March 30 to May 2, a diagnosis of invasive listeriosis infection was made in four CHVR patients who could have contracted illness from eating these cheeses during their hospital stays.

According to information from meal cards, the infected patients did consume cheese during their hospitalization but it is not possible to be certain that it was the cheeses in question.

Three of the people have recovered but one person with underlying health conditions has died.

Käserei Vogel informed the Federal Food Safety and Veterinary Office (FSVO) in Switzerland about the contamination.

FSVO, also known by its French acronym OSAV, Italian name USAV and under the German name BLV, told people not to consume the products concerned by the recall as they may pose a health hazard.

More than 20 items including sheep and goat cheese, brie and organic cheese sold across Switzerland have been recalled by the company. Cheeses can be identified as they have number CH-5707 on the packaging. Distribution also includes Belgium and Germany, according to the Rapid alert System for Food and Feed (RASFF) portal.

Denner, a supermarket in Switzerland, has recalled all expiration dates of “Denner Fromage de montagne de la Suisse centrale” because of detection of Listeria at the site of the dairy producer.

Migros, another retailer in the country, recalled all batches of five cheese products sold at different stores because of the problem.

about Listeria infections
Food contaminated with Listeria monocytogenes may not look or smell spoiled but can still cause serious and sometimes life-threatening infections. Anyone who has eaten any of the recalled products and developed symptoms of Listeria infection should seek medical treatment and tell their doctors about the possible Listeria exposure.

Also, anyone who has eaten any of the recalled product should monitor themselves for symptoms during the coming weeks because it can take up to 70 days after exposure to Listeria for symptoms of listeriosis to develop. 

Symptoms of Listeria infection can include vomiting, nausea, persistent fever, muscle aches, severe headache and neck stiffness. Specific laboratory tests are required to diagnose Listeria infections, which can mimic other illnesses. 

Pregnant women, the elderly, young children, and people such as cancer patients who have weakened immune systems are particularly at risk of serious illnesses, life-threatening infections and other complications. Although infected pregnant women may experience only mild, flu-like symptoms, their infections can lead to premature delivery, infection of the newborn or even stillbirth.