Table 1.

Overview of six studies on molecular typing of T. pallidum strains from neurosyphilis patients.

First author (citation)	Location	Specimen collection period	Specimen type	Specimen size	Typing system	Strain
Sahi et al. (47)	Seattle, USA, America	1999–2017	Whole blood, CSF	18	MLST	Eight patients had a 1.1.2 strain; no patients had a 1.3.1 strain; nine patients had a tp0705 type 2 strain.
Sahi et al. (47)	Seattle, USA, America	1999–2017	Whole blood, CSF	18	ECDCT	One patient had a 14d/g strain; 16 patients had a tp0548 type f strain.
Marra et al. (48)	Seattle, USA, America	1999–2008	CSF	84	ECDCT	22 patients had a 14d/f strain.
Dai et al. (50)	Shanghai, China, Asia	2007–2011	Lesion swab	4	ECDCT	Two patients had a 14d/f strain; two patients had a 19d/c strain.
Read et al. (51)	Sydney, Australia, Oceania	2004–2011	Lesion swab	2	ECDCT	Two patients had a 14d/f strain; two of six patients with strain type 14d/f developed neurosyphilis, compared with 0/85 with non-14d/f strains.
Molepo et al. (46)	Pretoria, South Africa, Africa	1999–2000	CSF	50	CDC	Seven patients had a 14a strain; four patients had a 3e strain; one patient had a 17e strain; one patient had a 2i strain.

CSF, cerebrospinal fluid; ECDCT, enhanced CDC-typing; MLST, multi-locus sequence typing.