Background: Salmonella enterica subsp. enterica serovar Infantis (antigenic formula 6,7,14:r:1,5) is a serovar of the O:7 (C1) serogroup. S. Infantis is commonly found in chickens and broiler flocks. In addition, outbreaks caused by S. Infantis have been associated with pet food and treats. In European countries, a multidrug-resistant (MDR) strain of S. Infantis was disseminated; this strain emerged from broilers in Hungary (Hungarian clone of S. Infantis). Resistant pattern of this Hungarian clone included resistance to: nalidixic acid, streptomycin, sulphonamide, and tetracycline. In Italy, an MDR strain of S. Infantis that showed resistance to ampicillin, chloramphenicol, streptomycin, sulphonamide, tetracycline, kanamycin and trimethoprim/sulfamethoxazole emerged in 2005-06.
NCBI PD link for serovar Infantis: https://www.ncbi.nlm.nih.gov/pathogens/isolates/#(taxgroup_name:%22Salmonella%20enterica%22)%20AND%20computed_types:(%22serotype=Infantis%22)
In the U.S. and Europe, it ranks among the top ten serovars. S. Infantis has been reported in North America (U.S. and Canada), South America (Argentina, Brazil), Oceania (Australia and New Zealand), Europe (The Netherlands, Finland, Hungary, and Russia), and Asia (Japan).
Genetic characteristics:
Animal reservoir: The main animal reservoir of serovar Infantis is poultry; however, at least one of Infantis clade is associated with swine.
Geographical distribution: Serovar Infantis is distributed globally and is a common serovar in a number of countries.
Outbreaks: Numerous outbreaks linked to poultry have been reported mainly in the US and Canada. Here are some examples.
Year | Location | Associated source | Number of cases |
| 2024 | US: multistate | Backyard poultry1 | 470 |
| 2019 | US: multistate | Raw chicken | 129 |
| 2017 | US: multistate | Papaya2 | 4 |
2013 | Germany | 267 | |
2013 | US: multistate | 158 | |
2012 | US: multistate & Canada | 49 | |
2012 | US: multistate | 195 | |
1999 | Canada | 30 |
1 Multiple serovars, including Salmonella Altona, Cerro, Enteritidis, Indiana, Infantis, Johannesburg, Mbandaka, and Typhimurium, were linked to this outbreak. The case number represents the total number of cases associated with the outbreak and does not specifically indicate the number of people infected by Salmonella Infantis.
2 This outbreak involved both Salmonella Newport (3 cases) and Infantis (1 case).
3 Salmonella Infantis, Lille, Newport, and Mbandaka were reported from 30 states.
4 Salmonella Infantis, Newport, and Lille were reported from 27 states.
Border rejections: Multiple border rejections linked to serovar Infantis have been reported. Majority of them are associated with poultry. Here are some examples.
Year | Exporting country | Importing country | Associated source | Product category |
| 2024 | Poland | Italy | Frozen chicken meat1 | Poultry meat and poultry meat products |
| 2023 | Poland | Germany | Dog chews | Pet food |
| 2020 | Brazil | Germany | Black pepper2 | Herbs and spices |
| 2020 | Russia | Finland | Maize | Feed materials |
1 Salmonella Enteritidis and Infantis were both found.
2 Salmonella Infantis and Panama were both found.
Recalls: Multiple recalls linked to serovar Infantis have been reported. Majority of them are associated with poultry. Here are some examples.
| Year | Location | Recalled food | Type |
|---|---|---|---|
| 2023 | Slovakia | Chicken eggs from Czech Republic | Eggs and egg products |
| 2023 | Czech Republic | Chicken breast from Ukraine | Poultry meat and poultry meat products |
| 2021 | US: WA | Uncured antipasto products | Meat and meat products (other than poultry) |
| 2021 | Norway | Frozen fish (Gourami) from Vietnam | Fish and fish products |
Relevant links: