Table 1.

Reported animal hosts and human-associated isolates of T. phagedenis and BDD-associated treponemes.

Host species	Disease or lesion type	Detected organism or group	Detection method	Region	Reference
Cattle	Bovine digital dermatitis	T. phagedenis, T. medium, T. pedis	Culture, PCR, sequencing, FISH	Multiple countries	Simon R. Clegg et al., 2016b; Döpfer et al., 1997; Klitgaard et al., 2013
Sheep	Contagious ovine digital dermatitis or foot lesions	BDD-associated treponemes	PCR, sequencing	Sweden/UK and other regions	Bernhard et al., 2021; Calvo-Bado et al., 2011; Frosth et al., 2012
Donkey	Keratoma or horn lesions	Treponema spp.	Culture, sequencing	UK	Paraschou et al., 2023
European bison	Digital dermatitis lesions	T. phagedenis and related treponemes	PCR, histology	Switzerland	Hoby et al., 2021
Wild elk/moose	Hoof disease or DD-like lesions	BDD-associated treponemes	Culture, PCR, sequencing	North America	Clegg et al., 2015; Han et al., 2019
Human	CSF from neurosyphilis patient	T. phagedenis	mNGS, phylogenetic analysis	China	Yuan et al., 2023^1

^1Yuan, C., et al. (2023). Case Report: Detection of Treponema phagedenis in cerebrospinal fluid of a neurosyphilis patient by metagenomic next-generation sequencing. Front. Cell. Infect. Microbiol. 13:1218049. doi: 10.3389/fcimb.2023.1218049.

This is the first documented case of T. phagedenis detection in human CSF in China; phylogenomic analysis showed it belongs to a human-associated lineage distinct from BDD-associated bovine strains.