S. Hartford¶

At a Glance


Antigenic Formula	`6,7:y:e,n,x`
Serogroup	O:7 (C1)
NCBI Pathogen Detection	View isolates

Background Information¶

Salmonella enterica subsp. enterica serovar Hartford (antigenic formula 6,7:y:e,n,x) is a serovar of the O:7 (C₁) serogroup. Serovar Hartford was previously recovered from non-outbreak cattle herds. Serovar Hartford was found as highly persistent in all low-a_w food ingredients.

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 six Hartford 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 inchicken, calves, horses, dogs, and wild animals such as wild black bears.

Geographical Distribution¶

Serovar Hartford has been found in the US, Canada, Australia, the UK, Hungary, and China.

Human/Animal Outbreaks¶

Year	Location	Associated Source	Number of Cases
2023	US: multistate	Not identified	54
2014	US: multistate	Organic sprouted chia powder¹	31
2010	US: multistate	Not identified	75
1995	US: FL	Unpasteurized orange juice²	62

¹ Salmonella Newport (20 cases), Salmonella Hartford (7 cases), or Salmonella Oranienburg (4 cases)

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.