Background information: Salmonella enterica subsp. enterica serovar Umbilo (antigenic formula 28:z10:e,n,x) is a serovar of the O:28 (M) serogroup. Serovar Umbilo is typically rare, with the ECDC recording 20 to 32 cases annually in the European Union/European Economic Area (including the United Kingdom until 2019) over the past decade (2014−2023). Public Health England found this serovar in curry leaves. In 2001, serovar Umbilo was found in organic rocket salad and pre-packaged ready-to-eat salads from an Italian producer in the UK, though it was not associated with any human infections. 

NCBI PD link for serovar Umbilo: https://www.ncbi.nlm.nih.gov/pathogens/isolates/#(taxgroup_name:%22Salmonella%20enterica%22)%20AND%20computed_types:(%22serotype=Umbilo%22)

Genetic characteristics: Through investigating the ongoing Umbilo outbreak which was described below, Rosner et al. found that clinical isolates from Denmark, Germany, and Austria were genetically similar, with a maximum pairwise distance of 4 allelic difference (AD) and a maximum distance of 2 AD from the reference sequence. Umbilo isolates that had a difference of more than 5 AD from the reference strain of the outbreak were not associated with the outbreak.

Animal reservoir: Serovar Umbilo was found in sheep, field lizards, and badgers.

Geographical distribution: Serovar Umbilo has been reported in Turkey, the US, South Africa, Kenya and Europe such as Denmark, Austria, Croatia, and Germany. 

Human outbreaks:

YearLocationAssociated sourceNumber of cases
2024Europe: multi-countryRocket salad (also known as arugula or rucola) from Italy

1581

1158 cases of serovar Umbilo have been reported across 3 EU/EEA countries. The cases were distributed as follows: Germany (117), Denmark (22), and Austria (19). Through EpiPulse, six other European countries each reported between one and 20 cases of serovar Umbilo.  

Border rejections:

Year

Exporting country

Importing country

Associated source

Product category

2024

Italy

Germany

Organic leaf spinach

Fruits and vegetables

Recalls: There have been no recent recalls linked to this serovar.

Relevant links:

  1. https://www.eurlsalmonella.eu/sites/default/files/2019-06/4%20Marie%20Salmonella%20contamination%20of%20%28imported%29fresh%20edible%20leaves%20190528_0.pdf
  2. https://pubmed.ncbi.nlm.nih.gov/31749479/
  3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9738870/
  4. https://webgate.ec.europa.eu/rasff-window/screen/notification/712437
  5. https://www.eurosurveillance.org/content/10.2807/1560-7917.ES.2024.29.46.2400728
  6. https://www.cdc.gov/nationalsurveillance/pdfs/2016-Salmonella-report-508.pdf
  7. https://www.foodsafetynews.com/2024/09/rare-salmonella-type-sickens-people-in-denmark-and-austria/
  8. https://www.sciencedirect.com/science/article/pii/S0362028X2203071X?via%3Dihub
  9. https://webgate.ec.europa.eu/rasff-window/screen/notification/716987