Study finds Salmonella in one-third of the EU's egg producers

The European Food Safety Authority (EFSA) study found that on average about one in five large scale commercial egg producers have laying hens infected with the Salmonella spp. pathogen.

The study is part of an EU-wide programme to improve food safety by first scientifically assessing the problems at the farm level and then determining what policies should be followed to reduce pathogen contamination throughout the supply chain. The studies could eventually lead to tighter regulatory controls on farms and processors.

Salmonellosis along with campylobacteriosis, are by far the most frequently reported food borne diseases in the EU. Both diseases are frequently caught through ingesting poultry and poultry products, such as eggs.

The EU-wide Salmonella baseline study was conducted on commercial large-scale laying hen holdings with at least 1,000 laying hens in the flock. The study was carried out in all the 25 member states, during the year to September 2005. Norway voluntarily participated in the study.

Based on a preliminary analysis by the European Food Safety Authority (EFSA), holdings having Salmonella enteritidis vaccinated flocks were less likely to test positive for the pathogen. However in the eight countries with both vaccinated and unvaccinated flocks, there was no different in the proportion of laying hens infected with Salmonella enteritidis.

At EU-level the presence of any Salmonella spp. was detected in about 31 per cent of the large-scale laying hen holdings surveyed. The number of positive samples in a holding varied between one and seven, with an important proportion of the holdings found positive on the basis of only one or two of the tested samples.

The testing did not find the Salmonella spp. species in any large scale commercial egg producers in Luxembourg and Sweden. The maximum level was found in Portugal, where about 80 per cent of the holdings had at least one hen test positive for the pathogen.

Salmonella Enteritidis and Salmonella Typhimurium was found in an average of 20 per cent of the large-scale laying hen holdings tested across the EU, with no cases found in Sweden, Ireland, Cyprus, Luxembourg, Latvia. Meanwhile, about 64 per cent of the egg farms in the Czech Republic tested positive, followed by Poland, where 56 per cent had one or the other species of the pathogen, and Estonia, with 52 per cent testing positive.

Holdings in the UK's were generally at the low end of the scale. About 12 per cent of holdings there tested positive for Salmonella spp. and eight per cent had at least one hen carrying either Salmonella Enteritidis and Salmonella Typhimurium.

After a salmonella scare of the late 1980s, the UK introduced strict legislation on egg safety.

In total, 5,317 laying hen holdings in the EU were tested in the study. The data focused on 4,797 holdings out of the total. Samples were taken from flocks of laying hens during the last nine weeks of their production.

The five most frequently isolated Salmonella species in the EU were, in descending order: Salmonella Enteritidis, Salmonella Infantis, Salmonella Typhimurium, Salmonella Mbandaka and Salmonella Livingstone.

The Community-wide study was done to estimate the prevalence of Salmonella in laying hen flocks, EFSA stated in releasing the results yesterday.

"The report contains the elements necessary for the establishment of the Community target for reduction of Salmonella in laying hens in accordance with Article 4 of Regulation No 2160/2003 of the European Parliament and of the Council on the control of salmonella and other specified food-borne zoonotic agents,"​ EFSA stated. The food safety agency expects to release a final report in October 2006.

According to an European Commission study published last year there were 192,703 reported cases of salmonellosis and 183,961 of campylobacteriosis cases reported during 2004 in the EU's 25 member states.

The statistics are in the European Commission's first report on the persistence in the EU of a range of zoonoses, foodborne diseases that are transmissible from animals to humans.

In 2004 the 25 EU countries reported a total of 6,860 outbreaks of zoonoses, with 42,447 people affected. By far the most frequently reported zoonotic diseases in humans are salmonellosis and campylobacteriosis, with the most deadly being listerious, the report found.

The EU's new zoonoses directive 2003/99/EC became effect 12 June 2004. Reporting according to the new rules started with data collected during 2005.

Zoonoses are diseases, which are transmissible from animals to humans. The infection can be acquired directly from animals, or through ingestion of contaminated foodstuffs. The seriousness of these diseases in humans can vary from mild symptoms to life threatening conditions.