TABLE 2.

Characteristics of laboratory tests used to diagnose arbovirus infections

Modality	Strength(s)	Weakness(es)	Sensitivity (%)	Specificity (%)	Reference(s)
Serology
ELISA
IgM capture	Decreased rates of false positivity from nonspecific antibody binding Decreased rates of false negativity from competition with preexisting IgG	Cross-reactivity with other members of the same family Persistence of IgM for >1 yr in some cases	CDC, 84	94	39, 62
			Commercial assays, 98–100a	92–97	24
Indirect IgG	Fourfold rise in titer identifies recent infection in the presence of preexisting IgM	Cross-reactivity with other members of the same family Long-lasting IgG from prior infections	CDC, 84		39
			LDT,c 40	94	58
			Commercial, 100a	83	42
IgG avidity assay	Allows for differentiation of recent from past infection	No commercially available tests
PRNT	Quantifies neutralizing antibodies	Requires highly trained staff
	Highly specific	Requires biosafety level 3 conditions
	Unaffected by history of prior infections	Slow turnaround time
IFA	As sensitive as MAC ELISA	Subjective interpretation	IgM, 96–100b	66–100	50, 66
			IgG, 92–100b	42–90	42, 57
MIA	Can be highly multiplexed	Not commercially available	98	96	42, 57
IHC	Useful for confirmatory diagnosis when tissue is available	Limited data on sensitivity and specificity
Molecular diagnostics
qRT-PCR	High analytic sensitivity and specificity Rapid turnaround time High throughput	Limited by short time period of viral replication	Serum, 14	100	70
			Whole blood, 87b	100	71
			CSF, 57	100	70
			Urine, 44	100	72
mNGS	No prior hypothesis on the target pathogen necessary	Low throughput
		Limited by short time period of viral replication

^aRelative to the CDC ELISA.

^bRelative to commercial or laboratory-developed ELISA.

^cLDT, laboratory-developed test.