Table 1.

Median clinical sensitivity of PCR methods for detection of spotted fever group and typhus group rickettsia in blood and skin/eschar biopsy samples^a

			Percentage clinical sensitivity
Sample	Rickettsia	Method	Number of assays	Median (IQR)	References
All	PanRick	All	145	23 (15–34)	[43,▪, 44,54]
	SFGR		331	48 (34–65)	[53, 54]
	TGR		257	5 (3–7)	[43▪,44]
Skin	All	All	233	43 (7–55)	[43▪,54]
	SFGR		101	67 (55–79)
	TGR		88	6 (5–6)
Blood	All	All	331	18 (4–30)	[43▪,44]
	PanRick		101	18 (12–23)
	SFGR		230	42 (24–56)
	TGR		169	3 (2–10)
All	PanRick	Real-time PCR	525	7 (4–23)	[43▪,44]
	SFGR	Real-time PCR	123	23 (14–33)
	TGR	Real-time PCR	257	5 (3–7)
	SFGR	Nested PCR	29	31 (31–31)	[53]
	SFGR	Conventional PCR	179	69 (61–80)	[53, 54]

^aDerived from studies for which serologic and PCR results on more than 10 patients were reported since 2013 identified using search terms ‘rickettsia’, ‘spotted fever’, ‘typhus’ and ‘PCR’, ‘real-time PCR’, ‘nested-PCR’, ‘qPCR’, ‘quantitative PCR’. PanRick – assays that target the genus Rickettsia; SFGR – assays that target spotted fever group rickettsiae; TGR – assays that target typhus group rickettsiae. Number of assays column includes total assays reported, including some on the same samples but different approaches or targets. IQR, interquartile range.