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Created by
Bella Chueh, last updated by Phutthaphorn Phaophu on Jun 23, 2025
2 minute read
Background: Salmonella enterica subsp. enterica serovar Rissen (antigenic formula 6,7,14:f,g:-) is a serovar of the O:7 (C1) serogroup. This serovar was first isolated from HOST in LOCATION in YEAR. Serovar Rissen is the 4th most common nontyphoidal Salmonella serotype isolated from human infections in Thailand and is also among the top 20 most frequently reported Salmonella serotypes in the United States.
NCBI PD link for serovar Rissen: https://www.ncbi.nlm.nih.gov/pathogens/isolates/#taxgroup_name:(%22Salmonella%20enterica%22)%20AND%20computed_types:(%22serotype=Rissen%22)
Genetic characteristics: Pornsukarom et al. reported that all Thai Rissen isolates in this study were multidrug-resistant and more than 90% were resistant to ampicillin, sulfisoxazole, tetracycline and streptomycin. Half of Rissen isolates in the USA were pan-sensitive and some of US isolates were resistant to only tetracycline. Wang et al. identified Rissen human isolates (anal swabs or feces) had the common resistance profile as ampicillin, trimethoprim-sulfamethoxazole, and tetracycline; respectively conferring to resistance genes blaTEM, tetA, and sul3.
Animal reservoir: Swine is the major animal reservoir of serovar Rissen, including pork production chain.
Geographical distribution: Serotype Rissen has been reported especially in Asian countries such as Thailand, China, and Vietnam, but also found in Italy, France, Spain.
Human outbreaks: XX outbreaks linked to Salmonella Rissen have been associated with SOURCES. Some examples are shown below.
Year | Location | Associated source | Number of cases |
2022 | Europe: multi-country | 72 | |
2011 | US: multistate | 106 | |
2008 | US: multistate | 28 | |
2008 | Europe: multi-country | 119 | |
2004 | France | 141 | |
2008-2009 | US: multistate | 87 |
Border rejections: Multiple border rejections associated with serovar Rissen have been reported. Here we selected five as examples.
Year | Exporting country | Importing country | Associated source | Product category |
| 2024 | Denmark | Finland | Feed materials | |
| 2022 | Spain | Belgium | Feed materials | |
| 2022 | Ukraine | Germany | Feed materials | |
| 2020 | Spain | Switzerland | Meat and meat products (other than poultry) | |
| 2020 | Belgium | Austria | Dog feed | Pet food |
Recalls:
| Year | Location | Recalled food | Type |
|---|---|---|---|
| 2019 | US: multistate | Pig ears1 | Pet treats |
1 This recall was caused by an multistate outbreak of many Salmonella serovars including Rissen linked to pig ears feeding to dogs.
Relevant links:
1. https://www.pasteur.fr/sites/default/files/veng_0.pdf
2. https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2021.702909/full
3. https://www.mdpi.com/2079-6382/9/10/660
4. https://www.veterinaryworld.org/Vol.16/May-2023/6.html
5. https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.968695/full
6. https://www.pagepressjournals.org/index.php/ijfs/article/view/9362
7. https://www.nature.com/articles/s41598-024-62141-9
8. https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2021.705044/full