S. Cerro¶

At a Glance


Antigenic Formula	`6,14,18:z4,z23:1,5`
Serogroup	O:18 (K)
NCBI Pathogen Detection	View isolates

Background Information¶

Salmonella enterica subsp. enterica serovar Cerro (antigenic formula 6,14,18:z₄,z₂₃:1,5) is a serovar of the O:18 (K) serogroup. This serovar emerged in cattle in the United States. According to the CDC report of 2011, this serovar ranked third among clinical-nonhuman sources. Hardly reported in human salmonellosis cases, but highly reported among dairy cattle.

Genetic Characteristics¶

Subtyping by pulsed field gel electrophoresis (PFGE) had identified a single predominant PFGE type on dairy farms in New York and Pennsylvania. Cohn et al. identified a large clonal clade comprised of predominantly sequence type 367 cattle and environmental isolates. Hypothetically disrupted coding sequences showed clade-specific losses of intact speC and sopA virulence genes in the large clonal S. Cerro clade, whereas the loss of intact vgrG, araH, and vapC was observed in all section Typhi S. Cerro isolates. Cummings et al. studied Cerro isolates collected in New York dairy herds and revealed that resistance patterns varied from zero to nine drugs, and drug-resistant isolates were found on eight (40%) of the farms that tested positive for serovar Cerro. Serovar Cerro was found to be polyphyletic with five phylogenetic groups and one stand-alone singleton that does not cluster with any other Salmonella Cerro isolates.

Animal Reservoir¶

Serovar Cerro is known as one of the cattle-adapted serotypes; however, at least one of its clades has been shown to be swine-associated.

Geographical Distribution¶

Serovar Cerro has been reported worldwide butmainly in the U.S.(from bovine samples). In addition, in Southern Italy, this serovar was described as endemic in the year 2000.

Human/Animal Outbreaks¶

Multiple outbreaks of human salmonellosis due to serovar Cerro have been reported. Below are a few examples.

Year	Location	Associated source	Number of cases
2024	US: Multi-state	Backyard poultry	470¹
2012	US: Arkansas	Eggs, chicken salad, person-to-person	6²
1985	US: New Mexico	Beef jerky	29

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 Cerro.

²The total case count was n=597, and a total of 60 and 106 Salmonella isolates were cultured from 56 (Prison A) and 99 patients (Prison B), respectively. Salmonella Cerro was isolated from 6 patients that were co-infected with other serovars, and 8 isolates were obtained from the egg samples.

Border Rejections¶

Year	Exporting country	Importing country	Associated source	Product category
2021	Ethiopia	Germany	Organic sesame seeds	Nuts, nut products and seeds
2020	Brazil	Germany	Black pepper¹	Herbs and spices
2020	Brazil	Germany	Black pepper²	Herbs and spices

¹ Salmonella Abaetetuba and Salmonella Cerro were both found.

² Salmonella Oranienburg and Salmonella Cerro were both found.

Recalls¶

Year	Location	Recalled food	Type
2019	US: multistate	Pig ear pet treats¹	Pet food
1985	US: New Mexico	Carne Seca²	Dried food

¹ Salmonella I 4,[5],12:i:-, Cerro, Derby, Infantis, London, Newport, and Rissen were found.

² This recall was caused by an outbreak described above.