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Background: Salmonella enterica subsp. enterica serovar Hartford (antigenic formula 6,7:y:e,n,x) is a serovar of the O:7 (C1) serogroup. It has been isolated from a dairy-producing environment. Serovar Hartford was previously recovered from non-outbreak cattle herds. Serovar Hartford was found as highly persistent in all low-aw food ingredients.
NCBI PD link for serovar Hartford: https://www.ncbi.nlm.nih.gov/pathogens/isolates/#(taxgroup_name:%22Salmonella%20enterica%22)%20AND%20computed_types:(%22serotype=Hartford%22)
Genetic characteristics: Serovar Hartford has been found to be polyphyletic with two lineages identified and one stand-alone singleton that does not cluster with any other Salmonella Hartford isolates. In a US study, serovar Hartford isolates were found to be pansusceptible to all antimicrobials tested using the Kirby-Bauer method. Additionally, all sixHartford isolates recovered from mesenteric lymph nodes on one of farms were indistinguishable based on pulsed-field gel electrophoresis analysis.
Animal reservoir: Salmonella Hartford was found in chicken, calves, horses, dogs, and wild animals such as wild black bears, and dogs.
Geographical distribution: Serovar Hartford has been found in the US, Canada, Australia, the UK, Hungary, and China, and the U.S.
Human Outbreaksoutbreaks:
| Year | Location | Associated Source | Number of Cases |
|---|---|---|---|
| 2023 | US: multistate | Not identified | at least 5354 |
| 2014 | US: multistate | Organic sprouted chia powder1 | 31 |
| 2010 | US: multistate | Not identified | 75 |
| 1995 | US: FL | Unpasteurized orange juice2 | 62 |
...
2 Salmonella Gaminara was also involved in this outbreak.
Border rejections: There have been no recent border rejections linked to this serovar.
Recalls: There have been no recent recalls linked to this serovar.
Relevant links and references:
- https://www.foodsafetynewsliebertpub.com/2023doi/03/fda-announces-new-salmonella-outbreak-other-investigations-continue/10.1089/fpd.2017.2303?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%20%200pubmed
- https://archivewww.cdcsciencedirect.gov/www_cdc_gov/salmonella/newport-05-14/index.htmlcom/science/article/pii/S0362028X22106150
- https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2025.1547190/full
- archive.cdc.gov/#/details?url=https://www.cdcpmc.ncbi.nlm.nih.gov/salmonellaarticles/2010/restaurant-chain-a-8-4-10.htmlPMC4652083/
- https://jamanetworkwww.mdpi.com/journals2076-2607/jama11/fullarticle2/188128403
- https://www.jstor.org/stable/pdf/24320783.pdf?refreqid=excelsior%3Ada8966aa9c6b88949ad11ca86de2b59c&ab_segments=&origin=&initiator=&acceptTC=1
- https://agriswww.faofda.org/agris-search/search.do?recordID=CN9211229gov/food/outbreaks-foodborne-illness/investigations-foodborne-illness-outbreaks
- https://wwwarchive.liebertpub.com/doi/10.1089/fpd.2017.2303cdc.gov/www_cdc_gov/salmonella/newport-05-14/index.html
- https://wwwarchive.mdpicdc.comgov/2076-2607/11/2/403#/details?url=https://www.fdacdc.gov/salmonella/food2010/outbreaksrestaurant-foodbornechain-illness/investigationsa-foodborne8-illness4-outbreaks10.html
- https://doi.org/10.1111/zph.13174jamanetwork.com/journals/jama/fullarticle/188128