Background: Salmonella enterica subsp. enterica serovar Mikawasima (antigenic formula 6,7,14:y:e,n,z15) is a serovar of the O:7 (C1) serogroup. While this serovar is very rare and hardly reported among human cases, it has caused two outbreaks (one in Norway and one in the UK). In the US there are no reports of S. Mikawasima in humans and animals in the last 10 years. In Malaysia, S. Mikawasima was reported from fish and from aquaculture systems; the reported strains showed resistant to up to four antibiotics (chloramphenicol, clindamycin, rifampicin, and tetracycline).
NCBI PD link for serovar Mikawasima: https://www.ncbi.nlm.nih.gov/pathogens/isolates/#(salmonella%20)%20AND%20computed_types:(%22serotype=Mikawasima%22)
Genetic characteristics: According to Novak et al. (2024), all the outbreak-related isolates (n=75) were resistant to amoxicillin/clavulanic acid, third-generation cephalosporins (36% to ceftriaxone and 47% to ceftazidime) and 40% of the isolates exhibited extended-spectrum β-lactamase production. In addition, whole-genome sequencing (WGS) analysis revealed that three outbreak-related strains have the same resistance gene profile [blaTEM-1B, aac(6')-Iaa, aac(6')-Im, and aph(2'')-Ib)].
Animal reservoir: Reptiles and fish have been reported as a reservoir.
Geographical distribution: S. Mikawasima appears to be only present in some countries in Europe and Asia.
Outbreaks: S. Mikawasima was associated with five outbreaks.
Year | Location | Associated source | Number of cases |
| 2020-2023 | Croatia | unknown | 27 |
| 2019 | UK, Sweden, France, Denmark and Ireland | unknown | 192 |
| 2018 | Germany, Sweden, Denmark, Czech Republic, Austria | unknown | 50 |
2013 | UK | unknown | 75 |
2012 | Norway | unknown | 13 |
1992 | UK | doner kebab | 9 |
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