Table 3. Rate and ratio of false Zika virus IgG–positive samples obtained with Euroimmun and Dia.Pro Zika virus IgG assays according to the non–Zika virus sample subgroup.

Test	Positive for dengue virus, collected before 2013	Positive for chikungunya virus, collected in 2014	Negative for Zika, dengue, and chikungunya viruses, collected at end of 2015
Euroimmun IgG test
False positivity rate, % (pos/pos + neg)	40% (14/35)	45.8% (11/24)	11.9% (5/42)
IgG S/C ratio of false-positive IgG, mean (range)	3.9 (1.1–6.7)	2.0 (1.2–2.9)	2.0 (1.3−3.7)
Dia.Pro IgG test
False positivity rate, % (pos/pos + neg)	40% (14/35)	58.6% (17/29)	21.4% (9/42)
IgG S/C ratio of false-positive IgG, mean (range)	9.2 (2.5–14.4)	3.1 (1.1–7.7)	4.3 (1.1–10.1)

*Neg, negative; pos, positive.