Table 2. Serologic and molecular diagnosis of scrub typhus cases in continental Chile, 2016–2018*.

Case no.	Serologic testing results
	IFA IgG†			ELISA IgG‡			ELISA IgM‡			Eschar molecular testing results
	Acute	Conv		Acute	Conv		Acute	Conv		PCR rrs	PCR 47kDa	qPCR rrs
1	256	256		+	+		+	–		+	+	+
2	<32	128		–	–		–	–		+	+	+
3	64	512		–	+		+	–		+	+	+
4	128	256		–	–		–	–		+	+	+
5	128	NA		+	NA		+	NA		+	+	+
6	128	NA		–	NA		–	NA		+	+	+
7	128	256		–	+		+	+		+	+	+
8	<32	NA		+	NA		+	NA		+	+	+
9	64	256		–	+		–	+		+	+	+

*Acute, acute-phase; conv, convalescent-phase; NA, not available; qPCR, quantitative PCR; +, positive; –, negative.
†Highest titer among 4 antigens.
‡Cutoff values calculated as mean optical density of negative local population + 3 SD.