Table 3.
Case studies investigating Campylobacter in squamates and links to human campylobacteriosis.
| Country | Findings | Campylobacter spp. | Squamate | Comments | Demographics | Reference |
|---|---|---|---|---|---|---|
| UK | Four isolates from ill patients were confirmed as reptile C. fetus strains using sap insertion PCR. Both strains (mammalian C. fetus and reptile C. fetus) were characterized by multilocus sequence typing to be sharing 92% nucleotide sequence identity. | Reptile C. fetus and classical mammalian C. fetus (C. fetus subsp. fetus and C. fetus subsp. venerealis) |
One snake (Heterodon nasicus) and one blotched blue-tongued skink (Tiliqua nigrolutea) | Reptile-like C. fetus strains have been isolated from cases of human disease. They showed capability of infecting humans despite having separate genomospecies. There was evidence of recombination. | Isolates from six clinically ill patients confirmed as reptile C. fetus strains using sap insertion PCR. | [44] |
| USA | Two Campylobacter spp. with markers of reptile origin were isolated from blood sample of a patient who was symptomatic due to recurrent bacteremia caused by C. fetus subsp. fetus. The second isolate was found 37 days after antibiotic therapy | Campylobacter fetus | Reptilian origin. Not reported how the patient acquired the pathogen. Chelonian cuisine or contact with pet reptile was suggested. | Pathogen was not able to be identified phenotypically at first. Molecular analysis (16S rRNA, then PCR, SapD sequencing) confirmed the pathogen was similar to C. fetus subsp. fetus and was of reptilian origin. | A febrile 27-year-old patient with precursor T-cell acute lymphoblastic leukemia. | [48] |
| China | Identification by multilocus sequence typing (MLST) 13 human cases of Campylobacter infection reported in Guangzhou in 2012 to 2013 |
Campylobacter fetus subsp. testudinum | Reptilian origin; Food or human–squamate contact was reported as most likely source as reptiles formed an integral part of Chinese cuisine. | Epidemiological data was unavailable for these nine cases. | 13 human cases of C. fetus reported. | [50] |
| Korea | Infectious spondylitis with bacteremia in a patient with chronic kidney disease was detected through 16S rRNA gene sequencing | C. fetus subsp. testudinum | Reptile | C. fetus spondylitis is a very rare disease. Confirmation of the identity of the squamate linked to the transmission was lacking. | 83-year-old male patient with end stage renal disease. | [46] |
| China | C. fetus subsp. testudinum strain 772 isolated from the ascites of a patient. Whole genome sequence of the C. fetus subsp. testudinum which is primarily isolated from reptile but can cause invasive infection in human was established. | C. fetus subsp. testudinum strain-772 | Reptilian food or human–squamate contact was reported as most likely source. | Complete genome sequence established. C. fetus subsp. testudinum from reptiles has zoonotic potential to cause infection in humans. | A patient with chronic kidney disease. | [51] |
| USA | Positive human infection with new subspecies of genetically distinct variant of C. fetus. | C. fetus subsp. testudinum subsp. nov | Reptile. Source reported to be related to traditional asian food or contact with reptile. | C. fetus association between reptiles and humans is well illustrated. Infection was related to exposure to foods of reptilian origin or due to human–reptile contact. | Positive cases in nine men of Asian origin, >60 years, with underlying illnesses | [47] |