Fontina Carrefour with E.Coli and Shiga toxins


The recent recall of a batch of ‘Terre d’Italia’ brand PDO Fontina cheese (Carrefour) contaminated with Shiga-toxin producing Escherichia coli (STEC) has raised new summer alarms. Insights and reflections.

E.coli, the common bacterium

The bacterium
Escherichia coli
belongs to the large family Enterobacteriaceae and normally behaves as a ‘commensal’. Because it colonizes the large intestine as early as the infant’s first months of life, it has a beneficial effect over time in maintaining the balance of the microbiota.

E. coli
is therefore physiologically and continuously present in the human intestine, as well as in that of animals. As a result, the presence of the bacterium in food products is an indication of fecal contamination that particularly affects agricultural commodities, including vegetables.

Genetic evolution of the species then led to the selection of particularly aggressive bacteria capable of causing infectious forms of urinary tract, meningitis, septicemia or gastroenteric diseases.

Shiga-toxins, the grave danger

STECs, that is, E. coli strains capable of producing Shiga-toxins, rank among the most dangerous food-borne bacteria. Bacteria are indeed capable of firmly adhering to the cells of the intestinal epithelium, and the toxins they produce quickly enter the bloodstream.

thus exert their action on target cells far from the intestinal tract, such as the endothelial cells lining the vessels of renal glomeruli and the small blood vessels of the colon. STEC infections are therefore characterized by diarrheal episodes sometimes complicated by intestinal bleeding (hemorrhagic colitis) and, in severe cases, acute renal failure. The actual failure is aggravated by concomitant hemolytic anemia and platelet deficiency, which combine to delineate the severe picture of the so-called Hemolytic-Uremic Syndrome (HUS).

SEU and hemorrhagic colitis can be fatal, or lead to serious consequences such as chronic renal failure and the need for a kidney transplant, especially if young children (usually around two years of age) or debilitated elderly people are affected. The severity of the disease leads public health authorities to the utmost severity if a food product is found to be contaminated with it. Thus, there are no tolerable microbial limits and the mere presence of STEC is sufficient to qualify a food as hazardous. (1)

Fontina DOP Carrefour and shiga-toxins, the uncontrolled risk

In the case of Terre d’Italia PDO fontina cheese (Carrefour), the presence of STEC bacteria can be reasonably traced to the use of cow’s milk. Many animals, ruminants especially, harbor Shiga-toxin-producing E. coli in their intestines without showing any symptoms of disease. Animals behave, in these cases, as ‘asymptomatic carriers.’ And their milk or meat–in the absence of proper testing–risks being released freely into the commercial circuit.

The food being recalled presents a greater hazard, as it is a Ready-to-Eat product, not subject to cooking before consumption. Heat treatments at temperatures above 70°C (that required to pasteurize milk or cook meats), conversely, are effective in destroying Shiga-toxin-producing E. coli stigmas.

Food safety must be guaranteed by all players in the supply chain. First and foremost by the OSA (Food Business Operator), but also by the distributor, all the more so when products are marketed under his brand name. Preventive microbiological testing would be sufficient to rule out the presence of such microorganisms on highly pathogenic foods.

In Val d’Aosta (or Val da Ossa), home of fontina cheese, however, European rules to guard food safety and the environment have repeatedly given way in recent years to the sinister interests of malfeasance. With the support of local politicians, who introduced derogations contrary to EU law. (2) And the culpable indifference of the judiciary, which – ignoring the rules that have been in force in Europe for at least twelve years – has come to acquit the production of fontina cheese on abusive premises. (3)

Dario Dongo


(1) Pursuant to the reg. EC no. 178/02, Article 14. For more details, see our free ebook ‘

‘Food safety, mandatory rules and voluntary standards.

‘, at

(2) See in this regard the articles


(3) Cf. reg. EC 852/04, Art. 6, and reg. EC 853/04, Article 4. See


+ posts

Dario Dongo, lawyer and journalist, PhD in international food law, founder of WIISE (FARE - GIFT - Food Times) and Égalité.