Background:  Salmonella enterica subsp. enterica serovar Thompson (antigenic formula 6,7,14:k:1,5) is part of Group O:7 (C1). Members of this group can be lysogenized by phage 14 (O:6,7 ––> O:6,7,14, former group C4). Salmonella enterica subsp. enterica serovar Cardiff has been combined with Salmonella enterica subsp. enterica serovar Thompson. 

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

Genetic characteristics:

Animal reservoir:

Geographical distribution: Serovar Thompson has been reported worldwide. 

Human outbreaks: 

Year
Location
Associated source
Number of cases
2024US: WAFood or drink from IHOP in Bellevue32
2023US: multistateFresh diced onions80
2021US: multistateSeafood115
2019US: multistateChicken134
2018US: multistateKratom2199
2018KoreaChocolate cake1,111
2017US: multistateImported maradol papayas3220
2006US: SCPeanuts100

1 The outbreak was associated with consumption of chicken purchased from an El Pollo Loco restaurant located in Barstow, California.

2 The outbreak involved six serovars including Salmonella I 4,[5],12:b:-, Heidelberg, Javiana, Okatie, Weltevreden, and Thompson. The case number here (n=199) represents the total cases in this outbreak, not just those infected with serovar Thompson.

3 Across 23 states, 220 infections were linked to five Salmonella serovars involved in the outbreak—specifically Salmonella Thompson (144 cases), Kiambu (54 cases), Agona (12 cases), Gaminara (7 cases), and Senftenberg (3 cases).

Border rejections: There have been no recent border rejections linked to this serovar.

Recalls: 

YearLocationRecalled foodType
2023US: multistateFresh diced onions1Fruits and vegetables
2021US: multistateSeafood2Fish and fish products
2017 US: multistateImported maradol papayas3Fruits and vegetables

1 This recall was caused by a multistate outbreak described above. On October 23, 2023, Gills Onions issued a recall of their fresh diced onion products.

2 This recall was caused by a multistate outbreak described above. On October 8, 2021, Northeast Seafood Products, Inc. issued a recall of their multiple products.

3 This recall was caused by a multistate outbreak described above. Five Salmonella serovars, Salmonella Thompson, Kiambu, Agona, Gaminara, and Senftenberg, were involved. Grande Produce, Agroson’s LLC, and Freshtex Produce, LLC issued recalls of their papayas. 

Relevant links:

  1. https://kingcounty.gov/en/dept/dph/health-safety/disease-illness/foodborne-illness-outbreaks/2024-feb-1-ihop
  2. https://www.cdc.gov/salmonella/outbreaks/onions-10-23/investigation.html
  3. https://www.cdc.gov/mmwr/volumes/72/wr/mm7219a2.htm
  4. https://www.cdph.ca.gov/Programs/CEH/DFDCS/CDPH%20Document%20Library/FDB/FoodSafetyProgram/EnvInvReports/ElPolloLoco_Chicken_Salmonella_Outbreak%20Report_Final_060820_redacted%20for%20posting.pdf
  5. https://archive.cdc.gov/#/details?url=https://www.cdc.gov/salmonella/kratom-02-18/index.html
  6. https://e-epih.org/journal/view.php?doi=10.4178/epih.e2019002
  7. https://archive.cdc.gov/#/details?url=https://www.cdc.gov/salmonella/kiambu-07-17/index.html
  8. https://outbreakdatabase.com/outbreaks/2006-salmonella-thompson-at-a-pumpkin-festival
  9. https://www.fda.gov/safety/recalls-market-withdrawals-safety-alerts/gills-onions-voluntarily-recalls-select-lots-fresh-diced-onion-products-because-possible-health-risk
  10. https://www.fda.gov/food/outbreaks-foodborne-illness/outbreak-investigation-salmonella-thompson-seafood-october-2021
  11. https://archive.cdc.gov/www_cdc_gov/salmonella/kiambu-07-17/advice.html