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S. Pomona

At a Glance
Antigenic Formula 28:y:1,7
Serogroup O:28 (M)
NCBI Pathogen Detection View isolates

Background Information

Salmonella enterica subsp. enterica serovar Pomona (antigenic formula 28:​y:1,7) is a serovar of the O:28 (M) serogroup. This serovar was first isolated 1941 from poultry. In a study of Salmonella from pet animals in China, serovar Pomona was identified as being the leading serovar identified in turtles (25%, 18/71).

Genetic Characteristics

Serovar Pomona has been found to be polyphyletic with two lineages identified. A study of Salmonella in pets found some multi-drug resistant isolates of serovar Pomona in cats and turtles and 6 isolates from turtles that contained extended-spectrum beta-lactamase genes. A study of clinical and environmental serovar Pomona genomes found that many of the environmental strains had genes for the type 4 secretion system (T4SS)and identified genes associated with virulence factors such as fimbriae production and invasion regulation (invA, invB, invC, fimA, fimC, fimD, and fimF) from clinical and environmental samples.

Animal Reservoir

This serovar has been commonly found in turtles and other reptiles, including alligators.

Geographical Distribution

This serovar has been reported from countries worldwide, including the US, the UK, Germany, China, Mexico, and Australia.

Human/Animal Outbreaks

Year Location Associated source Number of cases
2023 US: multistate Small turtles 801
2022 US: multistate Small turtles 282
2011-2013 US: multistate Small turtles 4733

1This outbreak was linked to serovars Pomona, Stanley, and Poona. 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 Pomona.

2This outbreak was linked to serovars Pomona (3 cases) and Stanley (25 cases).

3Multiple serovars were linked to a series of 8 outbreaks from 2011-2013 involving pet turtles. The other serovars linked to these outbreaks included Sandiego, Newport, Poona, I 4,[5],12:​i:-, and Typhimurium. The case number represents the total number of cases associated with the outbreak. Infection with Salmonella Pomona occurred during Outbreak 2 (23 people) and Outbreak 5 (120 people).

Border Rejections

There have been no recent border rejections linked to this serovar.

Recalls

There have been no recent recalls linked to this serovar.

References

  1. https://doi.org/10.1093/oxfordjournals.aje.a118994
  2. https://journals.asm.org/doi/10.1128/spectrum.03542-23
  3. https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2025.1547190/abstract
  4. https://doi.org/10.1080/09603123.2024.2336597
  5. https://doi.org/10.1016/j.scitotenv.2013.08.025
  6. https://doi.org/10.1177/0300985816677149
  7. https://www.cdc.gov/salmonella/outbreaks/turtles-08-23/index.html
  8. https://www.cdc.gov/salmonella/outbreaks/stanley-07-22/investigation.html
  9. https://archive.cdc.gov/www_cdc_gov/salmonella/small-turtles-03-12/index.html