Campylobacter declines but still most common foodborne disease

Campylobacteriosis remained the most commonly reported zoonosis despite decreasing from 2014, Salmonellosis increased slightly while STEC and Listeria cases were in-line with previous figures.  

Data comes from the European Food Safety Authority (EFSA) and the European Centre for Disease Prevention and Control (ECDC) annual report​ on zoonoses monitoring.

Zoonoses are diseases that can be transmitted directly or indirectly between animals and humans. Zoonotic foodborne diseases are transmitted by eating contaminated foodstuffs.

Spain improved its surveillance system which resulted in an increase of confirmed cases.

Deaths double from Campylobacter​

There were 229,213 reported cases of campylobacteriosis​ and it remains the most common foodborne illness, showing an upward trend since 2008 but decreasing 5.8% compared with 2014.

Reported deaths increased from 25 in 2014 to 59 which was similar to the average percentage over the last five years.

In 2015, 17 Member States (MS) reported 385 Campylobacter outbreaks compared to 444 in 2014.

They caused 1,421 cases of which 129 were hospitalised and one died. Germany reported the highest number (182) followed by Slovakia and France (103 and 32, respectively).

Different from previous years, the most frequently food vehicle associated with strong-evidence outbreaks was raw milk (14) followed by broiler meat (six).

Broiler meat is considered to be the most important single source of human campylobacteriosis. In 2015, 46.7% of the 6,707 samples were positive, which was higher than 2014.

The highest notification rates were in the Czech Republic, Slovakia, Sweden and the UK. The lowest were Bulgaria, Cyprus, Latvia, Poland, Portugal and Romania.

In Spain, an improved surveillance system resulted in an increase of confirmed cases by 15.3%.

High Salmonella notification rates from Czech Republic and Slovakia​

Salmonellosis​, the second most commonly reported foodborne disease in the EU, increased.

There were 94,625 cases in 2015 compared with 92,007 in 2014.

This was partly attributable to increased reporting to the ECDC (Croatia, Italy) as well as improvements in surveillance (France, Spain). France and Spain have had significant increasing trends since 2008.

Ten MS reported 126 fatal cases among the 16 that provided outcome of their cases. More than half (65 cases) were reported by the UK.

As in the previous year, the highest notification rates were by the Czech Republic and Slovakia while the lowest were from Portugal and Greece.

The large increase in notification rate in Bulgaria (48.3%) and France (15%) was accompanied by an increase in outbreaks and associated with changes in the laboratory and reporting procedures in France.

In Spain, the improved surveillance system led to an increase of confirmed cases by 36.5%.

In 2015, 23 MS reported 953 foodborne outbreaks caused by Salmonella involving 6,616 cases, 1,719 hospitalisations and three deaths.

As in 2014, Slovakia reported the highest number (232) followed by France and Poland (198 and 180, respectively).

S. Stanley was responsible for three strong-evidence outbreaks associated with turkey meat reported by Austria, Belgium and Croatia, which involved 215 cases with 46 being hospitalised.

The most common cause of outbreaks was Salmonella associated with eggs.

For 422 outbreaks, the link with the suspected vehicle could be established based on strong evidence.

Implicated food vehicles were mostly of animal origin, in particular eggs and egg products and pig meat (both accounting for 10% of all strong-evidence outbreaks), broiler meat (9%) and cheese (8%) followed by fish and fish products (7%) and milk and dairy products (5%).

Salmonella prevalence of 4.3% was described for dried seeds, mainly associated with samples collected during border inspection by Greece and the Netherlands.

Increased testing for other STEC serogroups ​

In 2015, 5,901 confirmed cases of shiga toxin-producing E. coli (STEC​) infections were reported and eight deaths.

The highest country-specific notification rates were in Ireland, Sweden, the Netherlands and Denmark.

Nine countries (Bulgaria, Croatia, Cyprus, Greece, Lithuania, Poland, Portugal, Romania and Slovakia) reported ≤0.1 cases per 100,000 population.

The most commonly reported STEC serogroup was O157 (41.7%), although its relative proportion compared to others declined.

This could be due to increased awareness and more labs testing for other serogroups. Serogroup O157 was followed by O26, O103, O91, O145, O146 and O128, said the report.  

The proportion of non-typable STEC strains continued to increase representing 11.9% of the reported cases with known serogroup. Non-typable STEC includes strains where the lab was not able to define the O-serogroup.

In 2015, 10 MS reported 50 foodborne outbreaks in which 572 people were affected and 52 hospitalised – a 32% increase compared with 2014.

Out of four strong-evidence STEC outbreaks; three were caused by STEC O157 and were reported by the UK.

Food vehicles implicated were ‘mixed leaf lettuce and raw minced lamb’, ‘chicken burgers and beef burgers’ and ‘various meat products’.

A large outbreak, involving 120 people in a University in Portugal, was caused by non-O157 STEC and associated with ‘mixed food’ (cooked hamburger and cooked onions).

Sprouted seeds are the sole category for which microbiological criteria for STEC exist in the EU and only two positive samples were found out of the 925 analysed by 12 MS.

For one sample, STEC O104:H4 was reported. This STEC serotype matched that which caused the large German outbreak in 2011.

However, the MS did not provide information on the enteroaggregative E. coli adhesion determinants, which characterised the German outbreak strain.

Listeria increasing in elderly population​

There has been a significant increasing trend of listeriosis​ between 2008 and 2015, with the proportion of cases in the over 64 age group increasing from 56.2% in 2008 to 64.1% in 2015.

Reported cases and their proportion have almost doubled in those over 84 years.

Mike Catchpole, chief scientist at ECDC, said the increasing trend of Listeria cases in the elderly population was ‘concerning​’.

“ECDC is working together with Member States to enhance surveillance for food- and waterborne diseases, starting with Listeria​, as earlier detection of relevant clusters and outbreaks can help prevent further cases.”​

The EU microbiological limit for L. monocytogenes in RTE food products on the market is 100 CFU/g.

Highest notification rates were in Spain, Malta, Sweden, Estonia and Finland. Spain improved the surveillance system in 2015, which resulted in an increase of confirmed cases by 36.5%.

Lowest rates were by Bulgaria, Croatia, and Romania with Cyprus and Luxembourg reporting no cases.

Listeriosis affected 2,206 people, causing 270 deaths in 19 member states – the highest since 2008. France reported the most fatal cases (75) followed by Germany (45).

In 2015, 14 Listeria outbreaks were reported by nine MS. Overall, they reported 230 cases of which 25 were hospitalised and four died.

In Italy, an outbreak associated with ‘pig meat and products ’ caused two deaths among 12 patients.

Germany reported the largest L. monocytogenes (serovar 4b) outbreak affecting 159 cases, of which only two were hospitalised. This was a strong-evidence outbreak associated with rice pudding in a school or kindergarten.

Dr Marta Hugas, head of biological hazards and contaminants at EFSA, said: “Listeria​ seldom exceeded the legal safety limits in ready-to-eat foods, the most common foodborne source of human infections. However, it is important that consumers follow manufacturers’ storage instructions and the guidelines given by national authorities on the consumption of foods.”​

Yersinia third most common​

Twenty-six MS reported 7,202 confirmed Yersiniosis​ cases making it the third most common reported zoonosis in the EU although there is no harmonised surveillance.

Yersinia enterocolitica was the most common species isolated from human cases. The most common serotype was O:3 followed by O:9 and O:5,27.

No fatalities were among the 4,304 confirmed cases for which this information was reported.

Ireland and the UK reported the highest proportion of Y. pseudotuberculosis infections, representing 7.7% and 6.8% of all confirmed yersiniosis cases, respectively.

In Spain, an improved surveillance system resulted in an increase of confirmed cases by 77.8% since 2013.

The highest country-specific notification rates were in Finland and Denmark.

Brucellosis​ and trichinellosis data​

Brucellosis​ is rare with 437 confirmed cases representing a stable rate compared with the last five years.

Almost 70% of human brucellosis cases were hospitalised with one death.

The highest notification rates and majority of domestic cases were reported as in previous years from Greece, Italy and Portugal which are not officially brucellosis-free in cattle, sheep or goats.

The high notification rate in Bulgaria, was due to an outbreak in July–August in the southwestern region, involving 33 cases infected with Brucella melitensis.

In 2015, 156 confirmed trichinellosis ​cases were reported. The EU notification decreased by 57.1% compared with 2014 which had the highest rate since 2010.

The decrease was mainly due to a reduced number of cases by Romania and Bulgaria. Lithuania had the highest notification rate due to an outbreak with 20 cases caused by wild board meat.

The trend for trichinellosis was influenced by a number of smaller and larger outbreaks with peaks often in January and February. The most common species was Trichinella spiralis followed by Trichinella britovi.

In 2015, 41 cases of congenital toxoplasmosis​ were reported in EU (Czech Republic, Germany, Hungary, Ireland, Lithuania, Poland, Slovenia and the UK).

France reported 216 confirmed congenital toxoplasmosis cases but this data came from 2014.

• If you missed part one of our analysis of the report with a focus on foodborne outbreaks - find it here​.