Almost 900 suspected foodborne outbreaks were reported in Germany last year including one due to Salmonella with almost 200 ill and another from Listeria that continued into this year with 100 infections.

Molecular surveillance plays an important role in detecting outbreaks. A decrease in transmitted data on pathogen typing has made it more difficult to detect outbreaks of E. coli or listeriosis, according to the Robert Koch Institute (RKI).

Data comes from the same report that revealed norovirus and Campylobacter were among the most commonly reported notifiable diseases in Germany last year.

In 2018, 886 potential foodborne outbreaks with 2,787 illnesses were notified to RKI compared to 875 outbreaks the year before. Six deaths were reported; two due to salmonellosis and four from listeriosis.

Almost 200 ill in Salmonella outbreak

In 377 outbreaks with 914 illnesses, Campylobacter spp. was specified, which was one less than 2017.

There were 364 outbreaks each with less than five people sick and 13 with five or more illnesses. An outbreak with 18 ill in Bavaria concerned a school class who visited a farm with insufficient or unheated raw milk listed as the infection vehicle.

Salmonella spp. was behind 274 outbreaks with more than 1,000 ill including 34 outbreaks with five or more cases. The number of outbreaks rose slightly compared to 2017. The increase was weaker than in 2017 when it was 23 percent. In past years until 2016, a decrease in such outbreaks had been seen.

One of the largest included 191 people in several federal states caused by Salmonella enteritidis complex type (CT) 1734. The probable vehicle of infection was barn eggs. During this outbreak, results of molecular typing of pathogen isolates were used to discover the association with 24 smaller outbreaks.

An outbreak of 30 patients in three federal states was caused by Salmonella Enteritidis (CT 1892) and linked to consumption of spaetzle, a type of egg noodle dumpling. An outbreak with 28 ill occurred at a nursing home and was caused by Salmonella Panama but an infection source was not found.

For enterohemorrhagic E. coli (EHEC), also known as Shiga toxin-producing E. coli (STEC), 55 outbreaks might have been foodborne with 172 people ill compared to 43 outbreaks and 110 ill in 2017.

Most affected only two or three people in private households. The largest occurred in a kindergarten in the state of Brandenburg wher 24 children and four adults fell ill but a source could not be found.

For Hemolytic Uremic Syndrome (HUS), four outbreaks were reported with nine infections. Three occurred in private households with raw milk, beef and goat meat suspected as a source of infection. One outbreak affected two children after a holiday together in Croatia.

More than 100 sick due to Listeria

Shigella spp. was suspected for 24 outbreaks with 97 sick and Yersinia enterocolitica for 11 outbreaks and 23 illnesses. For Shigella, the number of incidents rose from nine and illnesses from 21 in the previous year. Three outbreaks involved five or more patients with the largest affecting 28 people and linked to a daycare center. For Yersinia, most occurred in private households and the largest involved three people.

Thirteen outbreaks with 58 sick were caused by Listeria monocytogenes. In a 2018 to 2019 outbreak of listeriosis, a meat product was identified as the likely source. There were 109 cases between August 2018 and the end of March this year, with 87 infections last year.

Francisella tularensis and Clostridium botulinum were both behind two outbreaks with the former linked to 10 illnesses and the latter four.

Hepatitis A was linked to 46 outbreaks with 185 sick and Hepatitis E to eight and 17 illnesses. Two Hepatitis A outbreaks had a foodborne link. Twenty-nine cases were part of an international outbreak tied to eating frozen strawberries and 23 were associated with travel to or consumption of dates from Morocco.

Giardia lamblia could have caused 45 outbreaks with 116 patients but only two involved five or more patients. A total of 29 had a link to cryptosporidium spp with 100 ill compared to 22 outbreaks and 55 ill in 2017. Three outbreaks affected five or more people with the largest sickening 28 children that had visited a farm coming into contact with animals and drinking raw milk.

Confirmed foodborne stats

For 201 outbreaks (59 percent), no information was provided on suspected food. Among the remaining 139 incidents, meat products were most often linked to them followed by egg or egg products, milk or dairy, soups or sauces or fish or seafood.

In 14 of 18 foodborne norovirus gastroenteritis outbreaks involving 74 people no food information was provided. For four there was information on a suspected food such as meat products or milk or dairy products, fruit products, sugar products, chocolates, sweets or cereal products.

In total, 340 of the potential foodborne outbreaks were definitely food-related. They affected 1,337 patients. Among them were 165 outbreaks of Campylobacter spp. with 432 patients and 125 outbreaks with Salmonella spp. with 686 cases.

Nine EHEC outbreaks involved 47 people and four Listeria outbreaks affected 40 patients. Six Shigella spp. outbreaks had 14 patients and six people were ill in three Yersinia enterocolitica incidents.

A total of 68 people fell ill in eight Hepatitis A outbreaks and 12 were affected by Hepatitis E. Giardia lamblia was at fault for eight outbreaks with 17 ill and cryptosporidium spp. for 13 cases in five outbreaks.