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S. Reading

At a Glance
Antigenic Formula 1,4,[5],12:e,h:1,5
Serogroup O:4 (B)
NCBI Pathogen Detection View isolates

Background Information

Salmonella enterica subsp. enterica serovar Reading (antigenic formula 1,4,[5],12:e,h:1,5) is a serovar of the O:4 (B) serogroup. Serovar Reading was first isolated in 1916 from water in Reading, England. It has been implicated in foodborne illness, as well as a breast abscess, and a case of osteomyelitis.

Genetic Characteristics: Chen et al. found that serovar Reading ispolyphyleticwith three phylogenetic groups identified. A study of 988 isolates from the US described a highly adapted turkey clade among the 3 phylogenetic clades identified. They further identified an emergent subclade within the turkey clade with isolates from 2016-2019 and a found a difference in antimicrobial resistance and virulence factors gained from plasmids and phage-like sequences between the emergent and contemporary subclades. Multidrug resistant (MDR) isolates have been isolated fromturkey samples and beef feedlots with resistance to 3rd generation cephalosporins as well as ampicillin, chloramphenicol, streptomycin, sulphonamides, and tetracycline. MDR isolates were also identified during the 2018 US multistate outbreak associated with turkey products.

Animal reservoir: Poultry and swine are the implicated reservoirs for serovar Reading, and it has been the cause of death in turkey poults.

Geographical Distribution

S. Reading has been reported from countries worldwide including the US, UK, and and Australia.

Human/Animal Outbreaks

Several outbreaks linked to S. Reading have been reported.

Year Location Associated product Number of cases
2018 US-multistate Turkey Products 358
2016 US-multistate Alfalfa sprouts 361
2008 Finland Iceberg Lettuce 1072
1956-1957 US-multistate Unknown 283

1There were 30 cases associated with serovar Reading, 5 cases associated with serovars Reading and Abony, and 1 case associated with serovar Abony.

2This outbreak was linked to serovars Reading (30 cases) and Newport (77 cases)

Border Rejections

Year Exporting country Importing country Associated source Product category
2024 Germany Finland Turkey breast fillet Poultry meat and poultry meat products

Recalls

Year Location Recalled product Type
2022 Germany, Denmark Dried fenugreek leaves from India Herbs and spices
2018-2019 US-multistate Turkey products Poultry meat and poultry meat products
2016 US-multistate Alfalfa sprouts produce

References

  1. https://doi.org/10.1016/S0140-6736(01)29468-9
  2. http://ps.oxfordjournals.org/content/35/1/171.full.pdf+html
  3. https://journals.asm.org/doi/10.1128/mbio.01913-24
  4. https://doi.org/10.1128/msphere.00056-20
  5. https://www.fda.gov/animal-veterinary/national-antimicrobial-resistance-monitoring-system/2018-narms-update-integrated-report-summary
  6. https://doi.org/10.1038/s41598-017-14751-9
  7. https://www.cdc.gov/salmonella/reading-07-18/index.html
  8. https://archive.cdc.gov/#/details?url=https://www.cdc.gov/salmonella/reading-07-18/index.html
  9. https://archive.cdc.gov/#/details?url=https://www.cdc.gov/salmonella/reading-08-16/index.html
  10. https://doi.org/10.4315/0362-028X.JFP-10-455
  11. https://webgate.ec.europa.eu/rasff-window/screen/notification/563154
  12. https://pmc.ncbi.nlm.nih.gov/articles/PMC1951708/?page=10
  13. https://webgate.ec.europa.eu/rasff-window/screen/notification/672575