Listeriosis in Europe: the silent threat we must not ignore
Listeriosis highlights the fragility of our food safety systems. Even in Europe, where standards are advanced and controls are strict, vulnerabilities still exist. Ongoing vigilance, innovation, and awareness are vital to keep this silent danger under control.
In recent years, headlines about food poisoning have become common, usually linked to well-known bacteria such as Salmonella or Campylobacter. By contrast, Listeria monocytogenes rarely makes the news. Infections are relatively rare, yet each case can be devastating – with one of the highest mortality rates among foodborne diseases. Public health experts therefore regard it as a silent threat. Recent outbreaks in Europe – including those connected to cheese in France and ready-to-eat meals in Ireland – have already caused several deaths.
A worrying upturn
The latest report from the European Food Safety Authority (EFSA) and the European Centre for Disease Prevention and Control (ECDC), published in December 2023, confirms the rise of listeriosis. In 2023, EU countries recorded 2,952 invasive cases – the highest number since 2007, and 5.8% more than in 2022. While the overall incidence remains lower than that of other zoonoses, the steady rise over the past five years is worrying.
Ready-to-eat foods: a weak point
Most cases of listeriosis are linked to ready-to-eat (RTE) foods eaten without cooking. Smoked fish, cured sausages, sliced meats, soft cheeses, and packaged salads are classified as high-risk foods.
Almost 187,000 RTE food samples were analysed across 25 EU member states in 2023. Most categories showed contamination rates below 1%, but fermented sausages stood out – with nearly 15% of samples testing positive. Hard cheeses, fish, and unfermented meats had contamination levels around 1–2%. In factories, fish, seafood, and soft cheeses averaged 1% positive results, while ‘other products’ reached 2.8%.
A persistent and serious risk
Shelf-life studies confirm that Listeria does not disappear during storage. In some products, its growth is even promoted by factors such as pH and water activity. Although contamination levels are generally low, fish and seafood reached up to 10%, with similar levels observed in beef, pork, raw milk cheeses, fruit, and vegetables. Data from livestock is limited but suggests a very low presence.
Outbreak analysis reveals a paradox. In 2023, fewer outbreaks were reported than in 2022, yet the number of cases and hospitalisations increased. Outbreaks may be less frequent, but they are more severe. Experts emphasise that, alongside Salmonella Enteritidis, listeriosis remains one of the deadliest zoonoses in Europe.
High-risk groups include the elderly, pregnant women, newborns, and immunocompromised patients. For them, what may begin as a digestive problem can develop into meningitis or septicaemia.
Vigilance from farm to fork
Due to its severity, Listeria must be managed at every stage of the food chain. Industries and distributors implement strict systems, which are regularly inspected by health authorities. Consumers also play a crucial role in maintaining the cold chain, avoiding expired products, thoroughly washing fruit and vegetables, and exercising caution with high-risk foods, such as cheeses, smoked fish, and raw meat – especially among vulnerable groups.
An ongoing challenge
The 2023 data is an uncomfortable reminder: Listeria is a ubiquitous microorganism present in many environments, and it is here to stay. As we have seen, the number of cases has increased. It is therefore important to maintain all prevention strategies. The new EU regulations for controlling Listeria, which will come into force next summer, are a step in this direction. We recently published a post on this topic “Listeria: New EU regulations and how to stay ahead”.
In a sense, listeriosis symbolises the fragility of our food safety systems. Despite living on a continent with strict standards and advanced control systems, cracks can still be opened by a bacterium such as Listeria monocytogenes. This is why constant vigilance is required in all areas of the food chain, including industry, consumer habits at home and in restaurants, and raising awareness among all those involved.
We must advance our knowledge of the bacterium and its genetic characteristics and understand why it persists in food processing facilities, often forming biofilms that increase its resistance. We must also implement new control and elimination systems and methods, including innovative techniques such as whole genome sequencing and metagenomics.
Listeriosis may not grab headlines as often as other foodborne diseases, but its impact is severe. The steady rise in cases across Europe is a reminder that constant vigilance is essential. With new regulations, improved detection tools, and greater awareness from both industry and consumers, progress is possible. However, the fight against Listeria is one we cannot afford to ignore.
More information: EFSA
