EFSA-ECDC report for 2007: Salmonella remains most common cause of food-borne outbreaks

The European Food Safety Authority (EFSA) and the European Centre for Disease Prevention and Control (ECDC) have published their Community Summary Report on Food-borne Outbreaks in the EU in 2007. It shows that Salmonella remained the most common cause of food-borne outbreaks in the European Union, followed by food-borne viruses and Campylobacter. A total of 5,609 outbreaks were reported in 2007, which affected almost 40,000 people and caused 19 deaths. The report is based on a new robust reporting system distinguishing between possible and verified outbreaks. While the data vary considerably between Member States, a high number of reported outbreaks do not necessarily indicate a particular food safety concern but may rather be indicative that an effective national monitoring system is in place.

The report showed that Salmonella continued to be the most frequent cause of food-borne outbreaks accounting for four out of every ten reported outbreaks. Of the 2,201 Salmonella outbreaks reported, 590 could be verified by laboratory detection or by analytical epidemiological evidence. The remainder were also likely to be food-borne outbreaks, but no conclusive evidence was available. These outbreaks affected 8,922 people and caused ten deaths. Eggs or products containing eggs were the foods most frequently involved in the Salmonella outbreaks.

As in the previous year, viruses were the second most frequent cause of food-borne outbreaks. Altogether, food-borne viruses accounted for 668 reported outbreaks (of which 111 were verified) affecting over 3,700 people but causing no deaths. Crustaceans, shellfish, molluscs and buffet meals were reported as the sources of viral outbreaks. Campylobacter followed in the list of most common causes with 461 outbreaks, of which 29 (excluding a large waterborne outbreak) were verified, affecting 244 people. Broiler meat and other meats remained the most common food source of these outbreaks.

Bacterial toxins, such as those produced by Bacillus, Clostridium or Staphylococcus bacteria were the reported cause of 458 outbreaks in the EU and 4 deaths. Member States also reported outbreaks caused by other bacteria, such as E. coli, Yersinia and Listeria, as well as parasites. 17 waterborne outbreaks were also reported, affecting 10,912 people altogether.

In 2007, a total of 5,609 food-borne outbreaks were reported by EU Member States, a slight decrease from 2006. Of the total number of outbreaks, 36% (over 2000) were verified by laboratory detection of the pathogen in food or by epidemiological evidence showing a link between human infection and the food source. The specific cause of five of the 19 deaths caused by food-borne outbreaks could not be identified.

The majority of food-borne outbreaks in 2007 were outbreaks affecting more than one household. The contaminated foodstuffs were most commonly consumed in homes or in restaurants, cafés, hotels or other caterers. Other places where outbreaks occurred included schools, canteens and hospitals or medical care facilities.

The data on food-borne outbreaks in 2007 provided by 22 EU Member States varied significantly because national investigation and reporting systems are not harmonised within the EU. Numbers of verified outbreaks reported by Member States do not necessarily reflect different levels of food safety. It is more likely that a high number of reported outbreaks indicates the effectiveness of national monitoring systems. Norway and Switzerland also submitted data for the report.

Notes to editors

The Community Summary Report on Zoonoses in the EU in 2007 published in January 2009 evaluated the occurrence of zoonoses - animal diseases transmissible to humans - and zoonotic agents in animals, foodstuffs and feed. The report showed that infections from Campylobacter were again the most frequently reported zoonotic disease in humans across the European Union. The number of cases due to Salmonella infections in humans fell for the fourth year in a row and cases of Listeria infections remained at the same level as in 2006. This second part of the report covers food-borne outbreaks caused by biological agents. An outbreak is defined as an incidence, observed under given circumstances of two or more human cases of the same disease and/or infection where the cases are linked, or probably linked, to the same food source.

A new reporting system for information on food-borne outbreaks was used for the first time in 2007 to improve the quality of data at the Community level. Outbreaks were divided into possible and verified food-borne outbreaks. In verified outbreaks the link between human infections and the food source is supported by laboratory detection of the causative agent in the implicated foodstuff and/or analytical epidemiological evidence. Detailed information was only reported from verified outbreaks where the link between human infections and the food source is strong. Possible outbreaks are defined as outbreaks in which there is information linking the diseased persons to a possible common food vehicle but without conclusive evidence.

EFSA’s Unit on Zoonoses Data Collection supported by a Task Force comprised of Member State experts monitors data on zoonotic bacteria and parasites across the EU. Based Annual Community Summary reports EFSA makes recommendations on measures for preventing and reducing animal diseases transmissible to humans.