Background: Salmonella enterica subsp. enterica serovar Heidelberg (antigenic formula 1,4,[5],12:r:1,2) is a serovar of the O:4 (B) serogroup. S. Heidelberg is commonly found in poultry meat in North America. In the U.S. and Canada, it has caused numerous infections in chickens. In the U.S., this serovar has caused a number of outbreaks that included the recent outbreak (October, 2013), linked to raw chicken; this outbreak was caused by a multidrug resistant S. Heidelberg strain (resistant to ampicillin, chloramphenicol, gentamicin, kanamycin, streptomycin, sulfisoxazole, and tetracycline). S. Heidelberg accounts for the 8.6% of ceftriaxone-resistant Salmonella isolated from humans in the U.S. Recently, a phage typing scheme was developed for serovar Heidelberg in Canada; this scheme recognizes 49 phage types.
Animal reservoir: S. Heidelberg is mostly found in chickens and turkeys.
Geographical distribution: Mostly reported from North America, serovar Heidelberg is the second and seventh most common serovar isolated from humans in Canada and in the U.S., respectively. In Europe this serovar is rare (approx. 180 cases/year).
Outbreaks: Multiple Heidelberg outbreaks have been linked to poultry, most of them in the U.S.
Year |
Location |
Associated source |
Number of cases |
2013 |
US-multistate |
Raw chicken |
278 |
2011 |
US-multistate |
Kosher Broiled Chicken Livers |
190 |
2011 |
US-multistate |
Ground turkey |
136 |
2011 |
Europe |
In-flight catering from Tanzania to Europe |
22 |
2005 |
US-WI |
Pig roast |
25 |
2004 |
Canada |
Food handler |
45 |
2001 |
Australia |
Eggs |
12 |
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